Hot Education How-Tos
How To: Find the standard deviation with the Z-Score formula
In this tutorial, we learn how to find the standard deviation with the Z-Score formula. First, take your problem and write it out one by one underneath each other. Then, you will need to substitute the numbers in for the variables that are in the problem. Once you do this, you will follow the basic rules of math to find out what the answer to the problem is appropriately. Once you have done this, finish off the problem to find the answer, then you will have found the standard deviation using ...
How To: Find the area of a circle with a given radius
This video describes how to find the area of a circle given a radius of 4cm. The video begins by describing the formulas needed to find the area of the circle. The narrator cautions the viewer on a few common mistakes that people frequently make while using these formulas, such as not properly squaring the radius of the circle. The solution to the formula for a 4cm radius is 50.24 cm^2. The video then demonstrates that this value makes sense by overlaying a grid onto the circle and visually s...
How To: Find the area of an oblique triangle using formulas
In this tutorial the instructor shows how to find the area of an oblique triangle using different formulas. To find the area of an oblique triangle there are different formulae. The first formula to calculate the area of a triangle is area A = (1/2) * a * b * Sin(C), where a and b are the lengths of the two sides of the triangle and C is the value of the angle of the triangle that lies in between the two sides a, b. Now substitute these values in the given formula to find the area if you have...
How To: Find the volume of a cone quickly
For people who are interested in math or who need to know how to find the volume of a cone for any reason, whether it be homework or architecture, this video will show you how to do so. The formula for finding the volume of a cone is (1/3) pi x radius^2 x height. You can find the radius of your cone by finding half the length across the center of the circle which is the cone's base. After plugging in all the values into this equation, you will be able to find the volume of any cone when given...
How To: Find the Volume of Composite Figures (Also Called Composite Shapes)
Composite figures are composed of several geometric shapes and are three-dimensional shapes. The first composite shape is a combination of a rectangular prism and a pyramid. To find the volume of the entire shape you find the volume of each individual shape and add them together. The second figure consists of a cylinder and a hemisphere. Check out the video below for the full lesson.
How To: Solve linear equations in algebra
Who needs to watch the new "Iron Man" movie when you can solve linear equations? Brush up on your x's and y'x with this video, which teaches you how to solver a linear equation.
How To: Simplify a complex fraction w/ binomial denominators
To simplify a complex fraction, turn it into one fraction on the top divided into a fraction on the bottom. Once this is complete, you will turn the division into the two into a multiple by the reciprocal, factor, and then cancel. To make a division, find the lowest common denominator of both the top and the bottom. Once you get this division equation, look carefully at the equations. If something can be easily canceled, go ahead and cancel it out at this time. If you cannot cancel anything a...
How To: Convert fractions to decimals quickly and easily
This video shows you how to easily convert a fraction to decimals. To convert a fraction to a decimal, you simply divide the numerator by the denominator. You first need to move the decimal point in the divisor to the right until it is a whole number. Then, you have to move the decimal point in the dividend to the right by the same number of places the decimal point was moved. Then divide the new dividend by the new divisor. Please note you may need to move the decimal point two places to the...
How To: Find the surface area of a cone without slant height
Math always seems hardest until someone shows you how to do the problem and then it all seems just so simple. This video will walk you through the process of finding the surface area of a cone when you also have to derive the slant height. Use this example to help with your other cone problems.
How To: Graph inequalities on a number line
In this video, we learn how to graph inequalities on a number line. Inequalities have a greater than or less than sign instead of an equal signs. Remember that these are no different than figuring out how to graph normal equations. First, you will need to remove the single numbers from each side of the equation. Continue to do math on the equation until you figure out what 'x' is. From here, draw the numbers on your graph and then find the number that 'x' is greater to or less than. Use an op...
How To: Solve a word problem that asks you to convert yards into miles
Want to know how to express yards as miles? From Ramanujan to calculus co-creator Gottfried Leibniz, many of the world's best and brightest mathematical minds have belonged to autodidacts. And, thanks to the Internet, it's easier than ever to follow in their footsteps. With this installment from Internet pedagogical superstar Salman Khan's series of free math tutorials, you'll learn how to calculate how many yards make up a mile.
How To: Solve word problems involving domain and range
See how to find the domain and range of a function implied by a word problem with this free video math lesson. From Ramanujan to calculus co-creator Gottfried Leibniz, many of the world's best and brightest mathematical minds have belonged to autodidacts. And, thanks to the Internet, it's easier than ever to follow in their footsteps (or just finish your homework or study for that next big test). With this installment from Internet pedagogical superstar Salman Khan's series of free math tutor...
How To: Find the equation of a line given 2 points
This tutorial teaches you how to find a mathematical equation of a line given 2 points that exists on the line. The tutorial starts off with 2 points labeled (2,-4) and (3,6). The first step is to determine the slope of the line using the formula given in the tutorial in blue. The slope is then solved as 'm'. Plug the slope and the points into another formula given in green. The tutorial maker provides a tip that one can use x1 and y1 or x2 and y2, however, it must be consistent. After, solve...
How To: Find the area of a parallelogram using geometry
The video shows us how to find the area of parallelogram using geometry. Here in this video it is done by using an example where the parallelogram is given ABCD. The area of the parallelogram is base times height (bh). Here the base is given as 15 but the height is not known but it is represented by the segment BD. To find the value of h, let’s use right triangle BDC on the right side of the figure. Since base is 15 and the opposite side of the parallelogram is congruent, the hypotenuse of th...
How To: Calculate percent composition for chemistry
To calculate percentage composition we will take the example CO2 it stands for Carbon-Di-Oxide. It is the composition of Carbon and Oxygen. We have one carbon and its weight is 12.01 and 2 oxygen. So, we will multiply 2 with 16.00 which is the weight of the oxygen.
How To: Find y-intercept with an equation in point slope form
In this tutorial the instructor shows how to find the Y-Intercept given the equation of the line in Point-Slope form. He shows how to do this with an example. He tells to substitute the value of x to zero to find out Y-Intercept as Y-Intercept is nothing but the point where the line meets x-axis, where the value of x co-ordinate is zero. By watching this simple tutorial you can easily compute the Y-intercept of an equation in point slope form.
How To: Make a hand-powered fan
To build your own hand-powered fan, you'll need the following: 1 peanut butter jar lid
How To: Make Black Snake Fireworks With & Without Fire
In this video, I'll be showing you how classic black snakes work and how to make them at home. There are actually two methods covered in the video — one that uses fire and one that does not. So just choose the one that fits best for your situation.
How To: Make Gooey Green Slime Using Elmer's Glue and Borax
Remember the movie "Flubber," about mad professor Robin Williams and his gravity-defying invention of slime that could walk, talk, and transform into just about anything? Well, you can make a very similar type of green goo at home using stuff you already have lying around.
How To: Make a Double Heart-Shaped Homopolar Motor: The Valentine's Day Gift of Science!
Homopolar motors tend to be typecast as simplistic in nature, and that's true for the most part. The bare minimum requirements are a battery, conductor, and magnetic field, but when it comes to Valentine's Day, they're nothing short of complex.
How To: Use an aquarium filter to detect the presence of radon
This free video science lesson from YouTube's bionerd23 demonstrates a simple technique for detecting the presence of radon, a radioactive noble gass. For all of the relevant details and detailed, step-by-step instructions, as well as to get started trying this experiment yourself, watch this home-science how-to.
How To: Use the Entgegen-Zusammen naming scheme for alkenes in organic chemistry
What's in a name? Well, your chemistry grade, for one. In this free video science lesson from Internet pedagogical superstar Salman Khan, you'll learn how to .... Whether you need help studying for that next big test or could just use a hand finishing your homework, you're sure to be well served by this video lesson. For more information, including detailed, step-by-step instructions, take a look.
How To: Apply exponent rules in basic algebra
Looking for a guide on how to work with exponents in algebra? See how it's done with this free video algebra lesson. From Ramanujan to calculus co-creator Gottfried Leibniz, many of the world's best and brightest mathematical minds have belonged to autodidacts. And, thanks to the Internet, it's easier than ever to follow in their footsteps (or just finish your homework or study for that next big test).
How To: Use the quadratic formula to solve algebraic equations
Using the quadratic formula to solve equations may bring one, two, or no algebraic solutions. The quadratic formula is special to quadratic equations, which can have fractions, radicals, or neverending decimals. Learn how to solve quadratic equations using the quadratic formula with this free video algebra lesson. From Ramanujan to calculus co-creator Gottfried Leibniz, many of the world's best and brightest mathematical minds have belonged to autodidacts. And, thanks to the Internet, it's ea...
How To: Calculate percentage composition by formula
Could you use a little help figuring out how to find percentage composition? Watch this free video lesson. From Ramanujan to calculus co-creator Gottfried Leibniz, many of the world's best and brightest mathematical minds have belonged to autodidacts. And, thanks to the Internet, it's easier than ever to follow in their footsteps (or just finish your homework or study for that next big test). With this free math tutorial, you'll learn how to calculate percentage composition by formula.
How To: Figure out the domain & range of a piecewise function
Need to calculate the domain and range of a graphed piecewise function? Learn how with this free video lesson. From Ramanujan to calculus co-creator Gottfried Leibniz, many of the world's best and brightest mathematical minds have belonged to autodidacts. And, thanks to the Internet, it's easier than ever to follow in their footsteps (or just finish your homework or study for that next big test).
How To: Find oblique asymptotes of rational functions
This is a great instructional video on how to find oblique asymptotes of rational functions. Let us take the example f(x)= x square+4x-12 over x-6. Now we have to find the horizontal or oblique asymptotes of this rational function. The higher power here is x square which is at the top and hence we have to find oblique asymptotes of this function.When we divide x square+4x-12 by x-6 we get x=10 and the reminder is 48. Now you can easily write down the final answer. The oblique asymptote for th...
How To: Find surface area and volume of a sphere
In this how to video, you will learn how to find the volume of a sphere and surface area. Let's say you need to find the volume of a sphere with a surface area of 200 cm cubed. You will need to know the formulas for surface area and volume of a sphere. The formula for surface area is 4 pi r squared. The formula for volume is 4/3 pi r cubed. Plug in the surface area of 200 cm cubed and plug it into the formula. You should get an answer of about 3.99 cm. Now you just have to solve for the radiu...
How To: Do long multiplication
In this video the instructor gives you sample as of how to SLEP long multiplication. You start by breaking the numbers up to simpler forms. If you have a two digit number that your multiplying by a another two digit number you multiply the first two digit number and then buy the second digit of the second two digit number. You have to remember to carry the remainders. You then add your two multiplicative lines together giving you the sum. this can be done to cover any set of multi-digit numbe...
How To: Make hot ice using Sodium Acetate Trihydrate
This video in the Education category will show you how to make hot ice using Sodium Acetate Trihydrate. For this purpose you will need a pan, 100g of Sodium Acetate Trihydrate, 25ml of water, a wooden spoon and a glass. Take the Sodium Acetate Trihydrate and put 100g in the pan. Then place the pan on a stove and turn to medium heat. The Sodium Acetate Trihydrate will start to melt. In about five minutes when it has melted fully, add 25ml of water. Let the solution simmer for two minutes while...
How To: Make "Hot Ice" with Sodium Acetate Crystals
If you've ever used a heating pad or hand warmer, you essentially know what "hot ice" is. It's supersaturated sodium acetate, and it's actually fairly easy to make at home out of sodium acetate crystals. You can also make it out of vinegar and baking soda (directions at the bottom of this article).
How To: Use a TI-89 to calculate nCr
This video shows you how to do a mathematical representation on computing the nCr function using a TI-89 calculator. You can write the nCr notation in different forms. It can be simplified from nCr to C(n,r). The symbol can either be read "n choose r" or "n taken r at a time" which are from it's probability applications. On the example to find "26 choose 17", go to the Home screen of the TI-89 calculator and then go 2nd 5 which is Math. Go choose probability and then to nCr to type in (26,17)...
How To: Graph linear equations using y=mx+b
This video is an instructional guide about Graph Linear Equations presented in algebraic form. It is an easy to follow, step by step guide to solving such equations using the graph intercept formula. The first example equation is Y = 2x -1 over y = mx + b. The video then shows you how to breakdown the equation into manageable sums using fractions to represent the data, and then presents the formula for interpreting the answer from these sums onto the graph co-ordinates. The second and third e...
How To: Find a percentage of a number
This video in the Education category will show you how to find a percentage of a number. For example, what is 12% of 56? The simple way to do this is to find 10% of 56; which is 5. 6. Then you find 1% of 56 is .56. Then you add 10% plus 1% plus 1%, that is, 5. 6 plus .56 plus .56; which is 6. 72. And that’s the answer. The other way to do this is to make decimal out of 12; which is .12. Now multiply .12 by 56 and the product is 6. 72. These are the two methods of finding out a percentage of a...
How To: Solve an equation with a radical under a radical
In this video the instructor shows how to solve an equation with a radical under a radical. If you have an equation with a square root on both sides, with one of the sides having another inner square root under the original square root, it can be a little tricky to solve it.
How To: Understand the Pythagorean Theorem
In this video Ken teaches you about the Pythagorean Theorem. The Pythagorean Theorem is used to find the missing length of a side of a right triangle. By watching this video, you will learn how to find any the length of any side by using a simple mathematical formula. Ken walks you through various examples changing the dimensions of the triangle you are solving as well as changing the side you are solving. Ken even includes a real world application to further your understanding of the Pythago...
How To: Convert from cubic yards to cubic feet and inches
brettman6533 teaches you how to convert from cubic yards to cubic feet and inches. The volume of a cube is side cubed. If the side of a cube is 1 foot, then the volume would be 1 foot squared. Knowing that a foot equals 12 inches, you transform that into 1 times 12 in times 12 in times 12, which equals 1728 inches squared. If you want to convert a cubic yard, you have to remember 1 yard equals 3 feet. So now 1 yard squared is 1 times 3 feet times 3 feet times 3 feet, which is 27 feet squared....
How To: Factor and collect like terms
In this video, the instructor shows how to collect like terms and factorize. When you are given a linear equation, the first thing you do is to try to organize it. Pair up the like terms. Add the numerical coefficients of terms with the same variables. This is called collecting the like terms. In case you see any common factor across all the terms, pull it out and tag it to the parenthesis. In this way, you can factorize the equation. Next, bunch together your like terms and sum them up. The ...
How To: Determine the area of a trapezoid
Need to figure out the area of a trapezoid for a household project? Even if you just want to sound smart, there is a simple formula that can be used every time you need to find the area of a trapezoid. Try the formula and see how good you are at geometry.
How To: Shift a graph
This video will demonstrate exactly how to shift a graph on a x,y axis. When shifting a graph on the x axis you will need to replace x with x-h; where h is the variable to shift the graph. No matter how far you need to shift a graph, h is always the number of units you are shifting; shifting up or right is represented as a positive and down or left is negative. Just plug in your units into your equation and you will have your shifted graph.