Find a Percentage of a Number SWBAT use the percent formula to find a percentage of a number; use a percent proportion to find a percentage of a number
Think If Josie finds the perfect pair of shoes that are originally $29.99, but are on sale at 10% off, how much money will she save?
Percent Formula Percentage Formula Rate (r) · Base (b) = Percentage (p) Rate (r) · Base (b) = Percentage (p) rb=p rb=p Write the percent as a decimal (rate) Write the percent as a decimal (rate) Multiply it by the whole number (base) Multiply it by the whole number (base) This gives the percentage of the number This gives the percentage of the number
Percent Proportion percentage percent percentage percent base 100 base 100 Use cross products and solve for the percentage Use cross products and solve for the percentage =
Examples 40% of 45 3% of % of % of 30 60% of % of 90 8% of % of 50
Try These 28% of · · % of · · % of 92 3 · 92 3 · % of 2800 x/2800 = 28/ x = % of 4750 x/4750 =.2/ x = % of 92 x/92 = 300/ x =