Ratios
What is a ratio? Give an example.
A ratio is a comparison of two quantities. Example: The ratio of cats to dogs in a pet store is 3:2.
What is a unit rate? Provide an example.
A unit rate is a comparison of quantities where the second quantity is 1. Example: If you drive 60 miles in 1 hour, the unit rate is 60 miles per hour.
What is a percentage? Give an example.
A percentage is a way to express a number as a fraction of 100. Example: 50% means 50 out of 100.
If there are 3 apples and 5 oranges, what is the ratio of apples to oranges?
The ratio of apples to oranges is 3:5.
If a car travels 150 miles in 3 hours, what is the unit rate in miles per hour?
The unit rate is 50 miles per hour (150 miles ÷ 3 hours).
What is 25% of 200?
25% of 200 is 50 (0.25 × 200 = 50).
Simplify the ratio 12:16.
The simplified ratio of 12:16 is 3:4.
A store sells 12 cookies for $4. What is the cost per cookie?
The cost per cookie is $0.33 (or $4 ÷ 12 cookies).
If a shirt originally costs $40 and is on sale for 30% off, how much does it cost now?
The shirt costs $28 (30% off of $40 is $12, so $40 - $12 = $28).
A recipe calls for 2 cups of flour and 3 cups of sugar. What is the ratio of flour to sugar?
The ratio of flour to sugar is 2:3.
If you can buy 5 notebooks for $10, what is the cost per notebook?
The cost per notebook is $2 ($10 ÷ 5 notebooks).
A student scored 18 out of 20 on a test. What percentage did the student score?
The student scored 90%
If the ratio of boys to girls in a class is 4:5 and there are 20 boys, how many girls are there?
If the ratio of boys to girls is 4:5 and there are 20 boys, there are 25 girls (using the ratio 4:5, if 4 parts = 20 boys, then 5 parts = 25 girls).
A runner completes 10 kilometers in 50 minutes. What is the runner's speed in kilometers per hour?
The runner's speed is 12 kilometers per hour (10 kilometers ÷ (50 minutes ÷ 60) = 12 km/h).
If a population of a town is 2,500 and 10% of the population moves away, how many people moved?
250 people moved away (10% of 2,500 is 250).