PERCENTAGES 2

Expressing one quantity as a percentage of a second quantity To write one quantity as a percentage of a second quantity: Write the first quantity as a fraction of the second quantity Multiply by 100 to change the fraction into a percentage. 1 Write 42 as a percentage of 75. STEP 1: STEP 2: 2 There are 30 students in a class. Six of the students are left-handed. What percentage of the students are left-handed? STEP 1: STEP 2:

Percentage increase and percentage decrease John’s income increases from $20 000 a year to $23 000 a year. Calculate the percentage increase in his income. STEP 1: Increase = 23 000 – 20 000 = 3000 STEP 2: = 15%

2 The population of a village decreases from 785 to 634. Calculate the percentage decrease in the population. STEP 1: Decrease = 785 – 634 = 151 STEP 2: = 19.2%

Percentage profit and loss 1 A car salesman buys a car for $15 000 and sells it for $17 000. Calculate the percentage profit. STEP 1: Profit = 17 000 – 15 000 = 2000 STEP 2: = 13.3%

2 Cara buys a bike for $250 and then sells it one year later for $180. Calculate the percentage loss. STEP 1: Loss = 250 – 180 = 70 STEP 2: = 28%