- procedure for changing a percent to a decimal
- fraction/decimal/percent conversion chart
- unit fraction-conversion method
- unit fraction comparison
- The percent problem
- the amount; percentage
- percent; rate
- whole quantity; base
- warning: DO NOT ADD PERCENTS
6.8 Essential Ideas
Percent is the ratio of a given number to 100. This means that a percent is the numerator of a fraction whose denominator is 100.
To change from fractional form to decimal form:
Divide the numerator (top) by the denominator (bottom). Write as a terminating or as a repeating decimal (bar notation).
To change from fractional form to percent form:
First change the fraction to a decimal, and then move the decimal point two places to the right and affix a percent symbol.
To change from a terminating decimal form to fractional form:
Write the decimal without the decimal point, and multiply by the decimal name of the last digit (rightmost digit).
To change from a terminating decimal form to percent form:
Shift the decimal point two places to the right and affix a percent symbol.
To change from percent form to fractional form:
Write as a ratio to 100 and reduce the fraction. If the percent involves a decimal, first write the decimal in fractional form, and then multiply by 1/100. If the percent involves a fraction, delete the percent symbol and multiply by 1/100.
To change from percent form to decimal form:
Shift the decimal point two places to the left and delete the percent symbol. If the percent involves a fraction, first write the fraction as a decimal and then shift the decimal point.
The Percent Problem
A (this is the given amount) is P% (this is written as P/100) of W (this is the “whole quantity” and is follows the word “of”).
Here is the procedure to follow:
First, identify the percent; write it as a fraction P/100.
Next, identify the whole quantity; it is preceded by the word of.
Finally, the remaining quantity is the partial amount; it is the numerator of the second fraction in the proportion: P/100 = A/W.