Curated OER
Dividing Decimals 2.1
Occasionally, in mathematics, there are "short cuts" one can take. Sal explains a quick way to divide decimals numbers. He demonstrates that in certain cases, simply shifting the decimal point to the left will result in a correct answer.
Curated OER
How Do You Do Long Division with Decimals?
Review some long division that contains a decimal number. Do the division first and when that is completed then figure out where the decimal goes in the answer. Just don't let those decimals make you crazy about doing the long division.
Curated OER
How Do You Divide a Decimal by a Decimal?
Many learners would look at this decimal division problem and just skip it. Don't let them do that! Figure out how to help your learners master long division. The teacher helps make decimals and long division seem doable.
Curated OER
Multiplying Fractions and Mixed Numbers
Here is a great video explaining how to multiply a fraction by a whole number. Sal shows students how to put a whole number over 1 in order to multiply it by a fraction. He simplifies his answer and writes it as a mixed number.
Khan Academy
Multiplying And Dividing with Significant Figures
Sal takes out the big guns - or in this case, big calculator - in this video, which carries the concept of significant figures even further. Sal shows how to multiply and divide significant figures using both electronic and handwritten...
Curated OER
How Do You Multiply Decimals?
Find the product of numbers that have decimals. First, ignore the decimals and multiply the integers. Second, count the place values of the decimals for each value given. Third, add the values together. Fourth, place the decimal in the...
Khan Academy
Dividing whole numbers and fractions: t-shirts
There is no better way to present a math problem than within the context of a story. Sal explains how he divides a fraction to solve a word problem where he must determine how many shirts can be made with 48 yards of fabric. Problems...
Curated OER
How Do You Multiply Mixed Numbers?
Multiply two mixed fractions. First, change them to improper fractions. Now, multiply the numerator times the numerator and the denominator times the denominator. Oh, that's a big number. Reduce it. Now, change it back into a mixed...
Curated OER
How Do You Figure Out Which of Two Fractions is Bigger?
Trying to decide which method to use to compare the value of two fractions? You could find a common denominator, you could turn them into decimals, or you could cross multiply. Let's cross multiply because we like to multiply more than...
Curated OER
How Do You Figure Out a Percent of Change?
First identify the parts of the word problem. Next identify the variable, decide what formula to use, figure out the quantities, insert the quantities into the equation, and now solve. There are many parts to solving this word problem so...
Curated OER
How Do You Solve a Decimal Inequality Using Subtraction?
Isolate the variable to solve any equation. This equation happens to be an inequality but is solved no different than if it were just an equation. Use the subtraction property of inequality to solve this given problem. The numbers are...
Socratica
Using Scientific Notation
Scientists and engineers in every field use scientific notation. The Socratica video explains what scientific notation is and why people use it. Then, it offers examples of how to convert a number into and out of scientific notation....
Curated OER
Solving One-Step Equations 2
Help your students understand how to use their algebraic reasoning to solve a one-step equation, where they must solve for X. Add this video to a lesson or assign it as homework.
Curated OER
Two-Step Equations
Sal adds a few more steps to these problems as he solves algebraic equations with two steps - though he states that "there's more than one way to do it." Those who become confused by increasingly complicated algebra problems on a test...
Curated OER
How Do You Find a Missing Angle in a Triangle?
The interior angles of any and ALL triangles adds up to 180 degrees. So if given two of the angle degrees, is it possible to find the value of the third angle? Yes! Use the triangle sum theorem to solve for the missing angle. Watch this...