Math: Unit 9 Study GuideName ______

  1. Perimeter and Area: Be able to find the perimeter and area of polygons

Examples:

Find the perimeter and area of the polygon.

Number model: 5 + 5 + 9 + 9 = 28

Perimeter = 28 yd5 yd

Number model: 5 * 9 =459 yd

Area = 45 square yards

Try it.

Find the perimeter.

Number model: ______

Perimeter =______3 ft

Find the area of the polygon.7 ft

Number model: ______Area = ______

  1. Parentheses:Be able to insert parentheses to make number sentences true.

Example:12 = 15 - 2+1 => 12 = 15 –(2+ 1)

Try it:

  1. 40 + 30 *7 = 490
  2. 50 = 13 + 7 + 5 * 2
  1. Fractions: Be able to solve “fraction of” problems and rename fractions as decimals and percents. Be able to use a calculator to rename fractions as decimals or percents.

Example:

Sue made 3 out of 12 baskets in the basketball tournament.

  1. What fraction of the shots did she make? 3/12 or ¼
  2. What percent of the shots did she make?25%
  3. At this rate, how many shots would she make if she took 100 shots? 25

Try it:

Mark got 15 out of 20 problems correct.

  1. What fraction of the problems did Mark get correct? ______
  2. What percent of the problems did he get correct? ______
  3. At this rate, how many problems would he get correct if there were 100 problems? ______

Fill in the table of equivalent fractions, decimals, and percents.

Fraction / Decimal / Percent
⅖
½
.25
75%
.80

Use a calculator to rename the fraction as a decimal. ⅝ = ______

Use a calculator to rename the fraction as a percent. ⅙ = ______

  1. Multiplying Decimals: Be able to multiply percents (as decimals) by a whole number.

Example: Find 40% of 120 and 25% of 120.

Multiply 0.40 * 120 (use the calculator, if necessary) = 48

Multiply 0.25 * 120 (use the calculator, if necessary) = 30

Try it:

Given the percent, find the number out of the total.

60%
25%
15%
Total / 180