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How is multiplying by a decimal by 100 similar to multiplying a whole number by 100 How is it different?
10000
What decimal point is 100?
100 is a number, not a decimal point.
Why do you move the decimal point 2 places?
because you are multiplying or dividing by 102 = 100.
What percent is 0.00001?
You convert decimals to percents by multiplying the number by 100 or by simply moving the decimal point to the right 2 places. This would make the answer .001%.
Why isn't decimal numbers aligned when multiplying decimals?
When multiplying decimals, the decimal points are not only not aligned they are completely removed from the numbers to leave a multiplication of whole numbers which is done. Then the decimal point is put back into the answer by counting how many digits in total were after the decimal points in the original numbers and making the answer have the same number of digits after the decimal point. Example: 1.23 x 45.6 → 123 x 456 = 56088 1.23 has 2 digits after the decimal point, 45.6 has 1 digit after the decimal point making a total of 2 + 1 = 3 digits after the decimal point in the question, so there must be 3 digits after the decimal point in the answer → 1.23 x 45.6 = 56.088 Second example: 1.25 x 3.4 → 125 x 34 = 4250 2 digits + 1 digit = 3 digits in total in question must be after decimal point in answer: → 1.25 x 3.4 = 4.250 but normally any zeros that come at the end of a number after a decimal point are not written, so this would normally be written as: 1.25 x 3.4 = 4.25 A decimal number is a whole number divided by a power of 10, that is 10, 100, 1000, etc. This means that a decimal number can be written as an improper fraction with a power of 10 as the bottom number. So for the first example: 1.23 = 123/100 45.6 = 456/10 Multiplying the decimals together is the same as multiplying the two fractions together, which is done by multiplying the top numbers together and multiplying the bottom numbers together: 1.23 x 45.6 = 123/100 x 456/10 = (123 x 456)/(100 x 10) = 56088/1000 = 56.088
How is multiplying by a decimal by 100 similar to multiplying a whole number by 100 How is it different?
10000
What decimal point is 100?
100 is a number, not a decimal point.
What is it called when you move a decimal point to the right?
When you move a decimal point to the right you are multiplying a number by 10. For example, take 3.4. If you move the decimal point to the right you get 34. This is the same as: 3.4x10 = 34. Reversing this, you are dividing by 10 by moving the decimal point to the left. For example, take 73. If you move the decimal point to the right you get 7.3. This is the same as: 73/10 = 7.3. If you move a decimal point 2 spaces to the right, you are multiplying by 100, or more generally if you move the decimal point n spaces to the right, you are multiplying by 10^n.
What is the rule for multiplying by 100?
The rule is that you move the decimal point two positions to the right. If there is no existing decimal point then it is a whole number and the decimal point is at the far right as in 25 equals 25.0 Move the decimal point two places to the right and fill in any spaces with zeros. 25.0 X 100 = 2500.0 33.3 X 100 = 3330.0 42.87 X 100 = 4287.0
Why do you move the decimal point 2 places?
because you are multiplying or dividing by 102 = 100.
What percent is 0.00001?
You convert decimals to percents by multiplying the number by 100 or by simply moving the decimal point to the right 2 places. This would make the answer .001%.
Why isn't decimal numbers aligned when multiplying decimals?
When multiplying decimals, the decimal points are not only not aligned they are completely removed from the numbers to leave a multiplication of whole numbers which is done. Then the decimal point is put back into the answer by counting how many digits in total were after the decimal points in the original numbers and making the answer have the same number of digits after the decimal point. Example: 1.23 x 45.6 → 123 x 456 = 56088 1.23 has 2 digits after the decimal point, 45.6 has 1 digit after the decimal point making a total of 2 + 1 = 3 digits after the decimal point in the question, so there must be 3 digits after the decimal point in the answer → 1.23 x 45.6 = 56.088 Second example: 1.25 x 3.4 → 125 x 34 = 4250 2 digits + 1 digit = 3 digits in total in question must be after decimal point in answer: → 1.25 x 3.4 = 4.250 but normally any zeros that come at the end of a number after a decimal point are not written, so this would normally be written as: 1.25 x 3.4 = 4.25 A decimal number is a whole number divided by a power of 10, that is 10, 100, 1000, etc. This means that a decimal number can be written as an improper fraction with a power of 10 as the bottom number. So for the first example: 1.23 = 123/100 45.6 = 456/10 Multiplying the decimals together is the same as multiplying the two fractions together, which is done by multiplying the top numbers together and multiplying the bottom numbers together: 1.23 x 45.6 = 123/100 x 456/10 = (123 x 456)/(100 x 10) = 56088/1000 = 56.088
Which method you prefer for converting decimals to percents using equivalent fractions or multiplying by 100 why?
Multiplying by 100 is easier. Just move the decimal point two places to the right.
What does 100 mutiplied by14.5 equal?
When multiplying by 100, move decimal point two places to the right 100 x 14.5 = 1450
What is 100 times 0.40?
100 * 0.40 = 40 (tip: you can just move the decimal point two places to the right when multiplying by 100)
How do you turn a fraction into a decimal and a decimal in to a percent?
You turn a fraction into a decimal by dividing the top number by the bottom. And you turn a decimal into a percent by multiplying the decimal by 100.
How many centimeters is 1000000m?
1,000,000 meters is 100,000,000 centimeters because a meter is 100 centimeters and 1,000,000 multiplied by 100 is 100,000,000. Here I used a handy thing called benchmarks, if you are multiplying by a factor of 10 (i.e. 10, 100, 1,000, 10,000, etc) then you count how many zeroes are in the number (10 has one 0, 100 has 2 0's, etc) you move the decimal point in the number you are multiplying by the factor of ten to the right however many zeroes are in the number you are multiplying by. If there is no decimal point, you make one at the end, so 100 is 100.0, 100,000,000 is 100,000,000.0, etc.
