## Monday, January 17, 2011

### Mike's Final Percent Post

A percent means out of 100 , another name for hundredths and can be expressed as decimals or fractions.

REPRESENTING PERCENTS
Shade squares on a grid of 100 squares called a hundred grid to represent a percent. A completely shaded grid represents 100%. If you shade more than one grid, that represents a percent greater than 100%. To represent a fractional percent between 0% and 1%, you have to shade part of one square. Also, to represent a fractional percent greater than 1% you have to shade squares from the hundred grid to show the whole number, then shade part of a square the grid to show the fraction.

PERCENT OF A NUMBER

Use mental math strategies such as doubling, halving, and dividing by 10 to find the percents of some numbers. Write the percent as a decimal and then multiply by the number.

Example:14 1/2% of 60 = 0.145z60 = 8.7

COMBINING PERCENTS

To calculate the increase in any number, add the combined percents to the original number.

Example: 30% of 100=0.30x100=30, 30+100=130

Or multiply.

Example:130% of 100 = 1.30x 100= 115

Percents of percents can be used to determine amounts that result from consecutive increases or decreases.

Percent Review Video: