Hot Education How-Tos

How To: Multiply fractions

In this tutorial, we learn how to multiply fractions. First, you must know that the number on the top is called a numerator and the number on the bottom is the denominator. First, write out your equation with the fractions listed horizontally next to each other. After this, multiply the numbers straight across. The numerator will multiply with the numerator and same for the denominator. After this, when you get the final fraction you will need to reduce this further if you can. If you end up ...

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 interior & exterior angles of a triangle

In this tutorial, we learn how to find the interior and exterior angles of a triangle. I triangle has three angles and their measurement when added together will equal 180. For example, if one angle is 80 and another is 30, then start off saying the equation equals 180. Write in 80+30+X in front of the equals sign, then subtract the combined like terms from the 180. After this, you will have found the value of x, which will also be the measurement of the last angle. Make sure to write out the...

How To: Make your own nylon

In this tutorial, we learn how to make your own nylon. You will need: pipettes, pipette filler, forceps, beaker, stir rod, sebacoyl chloride and hexanediame solution. Now, pour some of the hexanediame solution into the small beaker. Add in a food coloring if you want to make this a specific color. After this, add in 4 cc's of sebacoyl chloride and carefully drip into the side of the beaker. You should see a layer of where the two liquids are after this. Now, take your tweezers and reach into ...

How To: Convert decimeters to kilometers in basic math

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 convert between decimeters and kilometers in basic mathematics.

How To: Add fractions with unlike denominators

In order to add fractions that are not alike, you will need to find the lowest common denominator. This is the least common multiple of the fractions. To add 2/3 plus 1/5, you will need to find the lowest common denominator. Here, it is best to think of all of the multiples of the denominators. If it helps, make a list. For 3, it is 3, 6, 9, 12, 15, etc. For five, the multiples are 5, 15, 20, 25, etc.

How To: Focus your laser to make it burn

In this video, we learn how to focus your laser to make it burn. The best spot for a laser to burn things is at its focal point. This is where the beam from the laser is at its smallest. If you hold a match in front of the beam, it will light it on fire as soon as it's in front of it. If you put two lasers next to each other going the same direction, it won't be able to burn because the light beam is too large. If you position the lasers so the light is smaller, then they can catch something ...

How To: Calculate the optimal angle for a projectile

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 four-part installment from Internet pedagogical superstar Salman Khan's series of free math tutorials, you'll learn how to find the optimal angle at which to launch a projectile.

How To: Find the circumference of a circle

In this video tutorial, viewers learn how to find the circumference of a circle. This task is very easy, simple and fast to do. To find the circumference of a circle, multiple Pi with the diameter of the circle. The value of Pi is 3.14. The diameter is equal to 2 times the radius. Simply multiply the radius by 2 to find he diameter. The diameter is the straight horizontal line in the center of a circle. This video provides a demonstration for viewers to easily understand and follow along. Thi...

How To: Make non-Newtonian slime mixing cornflour and water

In this tutorial, we learn how to make slime by mixing corn flour and water. To start, you will need corn flour, water, and two plastic containers. First, pour the corn flour into one plastic container and then add in some water with food coloring to the mix. After this, mix the combination together until it makes a paste. Add more water or corn flour as you mix. When finished, grasp the mix in your hands and it will start to turn into slime! You can color this with any color food coloring, b...

How To: Solve a quadratic equation by completing the square

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 tutorials, you'll learn how to solve quadratic equations by completing the square in intermediate algebra.

How To: Solve word problems containing radical equations

See how to unpack and solve a word problem containing radical equations with this free video math lesson from Internet pedagogical superstar Simon Khan. 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: Make (non-Newtonian) Oobleck from corn starch & water

Mr. O shows his audience in this video how to make oobleck, a slime-like substance which has a variety of unique properties. For this project, you will need a mixing bowl, food coloring, corn starch, a measuring cup, and water. First, color the water with food coloring to a color which is much darker than the color you would like. You will need the correct ratio of water to cornstarch, in a 1 to 2 ratio. Add some water to the bowl and add the cornstarch, then add the rest of the water. Finall...

How To: Cite scholarly journal articles in MLA format

This video shows viewers how to properly cite scholarly journal articles in the MLA format. In your works cited page, the citation should begin by placing the author's last name first, followed by his first name. If there are multiple authors, all subsequent authors should have their first name first followed by their last name. Placing a period after this, the next item is the title of the article, placed in quotation marks and followed by a period. The name of the scholarly journal is place...

How To: Find the equation for a growth pattern

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 tutorials, you'll learn how to find an equation that describse the growth pattern of a sequence of blocks.

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: Factor trinomials by grouping in algebra

Learn how to factor trinomials using the grouping method in 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 study for that next big test).

How To: Apply the Pythagorean theorem

Meet the Pythagorean theorem—an indispensable tool for any budding geometer. The Pythagorean theorem will allow you to measure the hypotenuse or any other side of a right triangle when the length of its other two sides are known. For specific, step-by-step instructions on how to use this useful formula, usually given as a^2+b^2=c^2, where c^2 is equal to the length of the hypotenuse, watch this free video geometry lesson.

How To: Find the inverse of a function in algebra

Need a little help figuring out how to find the inverse of a function in algebra? 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 the inverse of a given algebraic fun...

How To: Calculate the height and volume of a pyramid

Need to know how to calculate the height and volume of a pyramid in geometry? 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 eigenvectors and eigenspaces of a 2x2 matrix

Need help figuring out how to find eigenvectors and spaces for 2x2 matrices in linear algebra? 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 tutorials, you'll see...

How To: Increase a number by a percentage in basic arithmetic

Need to know how to grow a quantity by a percentage? Learn how. 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 tutorials, you'll learn how to increase a number by ...

HowTo: See Invisible Magnetic Fields

"Magnetic fields are everywhere- you just can't see them." The science-inspired-art project, Magnetic Movie, by Semiconductor, demonstrates the imaginary "secret lives of invisible magnetic fields". Don't miss it - it's an amazing project. The magnetic fields are beautifully depicted. However, they are indeed imaginary.

How To: Do normal probability calculations on a calculator

Probability computation is a complex process and even using a calculator can be difficult. But normal probability calculations can be performed quickly with the help of calculator once you know how to use it. So when you have to calculate a probability from a normal distribution you can use the functions on your scientific calculator. You can use the normal CDF function from you calculator to compute the area under a normal curve. The function requires lower band and upper band values, the me...

How To: Apply the distributive property in math

To solve simple algebraic expressions you have to use different properties. Distributive property is one among them. To apply distributive property in a algebraic expression multiply each term inside the parenthesis by the outside term. In this way you are distributing the outside term to all the inside terms and removing the parenthesis. Hence it is called distributive property. After multiplying add the like terms to simplify it further. Care should be taken to ensure the proper sign change...

How To: Make blue phosphorescent glow-in-the-dark powder

Making a blue glowing substance is easy, as long as you already know the secret to making green luminescent phosphorescent glow powder. By watching the green glow-in-the-dark procedure, you know that you will need strontium nitrate, aluminum nitrate, europium and dysprosium nitrates, and nitric acid. That will make a green glow, but if you want to make a blue version, it's a relatively easy fix...

How To: Find the North Star from the Northern Hemisphere

In this how to video, you will learn how to find the North Star in the northern hemisphere. To do this, you must know how to locate the Big Dipper and the Little Dipper. The Big Dipper is one of the brightest constellations in the sky. You can use this constellation to find the location of the north star. The two stars at the cup of the Big Dipper will point towards Polaris, also known as the North Star. The North Star is the end of the handle of the Little Dipper. This will be helpful if you...

How To: Divide exponents with the quotient rule

Exponent of a number is nothing but the number multiplied to it self the exponent number of times. So five squared it equal to five multiplied to it self. Now when an exponential number is divided with another such number the result is the number raised to the different of the exponents. That is the ratio of x raised by a to x raised by b is x raised to (a-b). Similarly if we multiply a exponential number with other such number, the result is equal to that number raised to the sum of exponent...

How To: Do a flaming ice experiment

In this fascinating "how to" video, you will see how a simple process creates the illusion of ice that is burning. Only a few items are needed to enact this scientific experiment. As the narrator describes, "Calcium carbide reacts with water to form acetylene gas." To illustrate, the video shows a bowl of ice cubes, to which the special ingredient is added. As the ice melts into water, it reacts with the calcium carbide, forming the high flammable acetylene gas, which is often used in welding...

How To: Find the average value of a function over an interval

When you have to find the average of two or five numbers then you have to add all the numbers and then divide then by two or five respectively. However in the case of the function you have infinite many values over any interval. But it is not possible to add all and then divide by infinity. Therefore you have to calculate in a different way. Imagine that you have to find the average of y=f(x). Then you have to average it from the interval from ‘a’ to ‘b’. The inner area under the curve shall ...

How To: Make classroom pointer sticks

Shelley Lovett with Child Care Land demonstrates how to make your own classroom pointer sticks. You can use pointer sticks as a prompt to help enhance learning in your classroom. You can make the pointers in accordance with holiday seasons. To make a pointer, you will need a 12-inch wooden dowel, an unfinished wooden shape, paint and accessories for decoration. First, paint your dowel and wood topper in your desired color. Next, using a hot glue gun, glue the shape to the dowel. Apply embelli...

How To: Figure out the area of quadrilaterals

Quadrilaterals are four sided shapes that are closed. They are polygons. Quadrilaterals can be classified broadly in two ways. If the quadrilateral has a two pair of parallel sides then it falls in to the parallelogram category. Further now it can be broken down in to other shapes like square, rectangle, rhombus. If it has only one pair of parallel side then it falls into the trapezoid category. To compute the are of a trapezoid first you need to know the lengths of the parallel sides. Add th...

How To: Use cross products to solve proportions

To solve a proportion for a variable you should employ cross multiplication. The basis of cross multiplication is the property which states that the product of the numerator of one fraction and the denominator of what it is set equal to is equal to the product of the remaining denominator and numerator. For example if you have x/15=21/45 you simply need to multiply x by 45 and 15 by 21 then set them equal to each other. The result of this is 45x=315. To solve this new problem for x, divide bo...

How To: Simplify algebraic expressions with negative exponents

This video explains the process of simplifying an algebraic expression with negative exponents. The video starts with an example of such an algebraic expression; the expression contains negative powers in both the numerator and denominator. The location of the negative exponents is first pointed out visually. Next, it is observed that there are like based or variables in both the numerator and denominator; however, it is explained that the numerator must first be expanded before the expressio...

How To: Measure pH levels with paper and meters

If you want to know the best way to get an accurate pH measurement, this shows the lab equipment needed and the processes used. When doing chemical reactions, sometimes the acidity or the basicity is important. This is usually defined as pH and measuring it can be very useful for getting the reaction right. There are a few ways to measure pH, and the simplest, cheapest, most reliable method is paper. But that's not all. See a whole lot of ways in this two-part video.