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This page provides a list of educational videos related to Multiplying Decimal Numbers. You can also use this page to find sample questions, apps, worksheets, lessons , infographics and presentations related to Multiplying Decimal Numbers.
Multiplying and Dividing Decimals | 7.NS.A.2c | 7th Grade Math
By ParksMath | Todd Parks
ParksMath explains how to multiply and divide decimals numbers without the use of a calculator. Understanding how to change a decimal number so that it is an integer, makes multiplying and dividing decimals much easier. This quick tutorial will give you thee tools that you need to find the product or quotient of any decimal number.
Dividing Scientific Notation | MathHelp.com
By MathHelp.com
To multiply numbers that are in written in scientific notation, such as 1.4 x 10 to the -2nd times 5.3 times 10 to the 6th, we first multiply the decimals, in this case 1.4 times 5.3, to get 7.42. Next, we multiply the powers of 10, in this case 10 to the -2nd times 10 to the 6th. Notice that we’re multiplying two powers that have like bases, so we add the exponents and leave the base the same, to get 10 to the -2 + 6, or 10 to the 4th. So we have 7.42 times 10 to the 4th. Finally, we’re asked to write our answer in scientific notation. Notice, however, that 7.42 times 10 to the -4th is already written in scientific notation, because we have a decimal between 1 and 10 that is multiplied by a power of 10. So we have our answer.
Multiplying and Dividing Decimals | 7.NS.A.2c | 7th Grade Math
By ParksMath
ParksMath explains how to multiply and divide decimals numbers without the use of a calculator. Understanding how to change a decimal number so that it is an integer, makes multiplying and dividing decimals much easier. This quick tutorial will give you thee tools that you need to find the product or quotient of any decimal number.
One-step multiplication and division equations with fractions and decimals
By Khan Academy
Learn how to solve equations in one step by multiplying or dividing a number from both sides.������������These problems involve decimals and fractions.
Multiplying Decimals - On a Place Value Chart (5.NBT.B.7)
By Worksheets and Walkthroughs
This video walkthrough lesson with corresponding worksheets investigates what happens on a place value chart as we multiply a decimal by a single digit number in a story problem format. Place value disks are used to represent values on a place value chart.
Multiplying and Dividing by Powers of 10
By jimbabweiberg
The instructor uses an interactive white board to show that multiplying a decimal by 10 100 1 000 or 10 000 moves the decimal one two three or four places to the right. He displays a calculator to show this as well. He also explains and shows that dividing by a power of 10 moves the decimal place to the left according to the number of zeros in the number you are multiplying by.
Understanding moving the decimal
By Khan Academy
You will notice in this word problem that moving the decimal to the right the same number of times as the number of zeros you multiplying by gets you the answer you desire. Check this out!
Multiplying and dividing with significant figures | Decimals | Pre-Algebra | Khan Academy
By Khan Academy
This video takes us through some real world examples of when we should use significant figures when multiplying and dividing. An important note: never consider significant figures until you have reached your FINAL ANSWER. Otherwise, rounding too early will produce more uncertainty about your solution.
Multiplying Scientific Notation | MathHelp.com
By MathHelp.com
In this example, which involves natural logarithms, we’re asked to solve each of the following equations for x, and leave our answers in terms of e. To solve for x in the first equation, ln x = 3, we simply switch the equation from logarithmic to exponential form. Remember that ln x means the natural logarithm of x, and a natural log has a base of e. So, to convert the given equation to exponential form, remember that the base of the log represents the base of the power, the right side of the equation represents the exponent, and the number inside the log represents the result, so we have e…to the 3rd…= x, and we’ve solved for x. Notice that our answer, e cubed, is written in terms of e, which is what the problem asks us to do. Now, let’s take a look at the second equation, ln x squared = 8. Again, we solve for x by switching the equation from logarithmic to exponential form. Ln x squared means the natural logarithm of x squared, and a natural log has a base of e. So, converting the equation to exponential form, we have e…to the 8th…= x squared. Next, since x is squared, we take the square root of both sides. On the right, the square root of x squared is x. On the left, however, there are a couple of things to watch out for. First, remember that the square root of e to the 8th is the same thing as e to the 8th to the ½, which simplifies to e to the 8 times ½, or e to the 4th. Also, remember that when we take the square root of both sides of an equation, we use plus or minus, so our final answer is plus or minus e to the 4th = x.
Units of Measurement | MathHelp.com
By MathHelp.com
This lesson covers vertical angles. Students learn the definition of vertical angles and the vertical angle theorem, and are asked to find the measures of vertical angles using Algebra. Students also solve two-column proofs involving vertical angles.
