Math Problem Solving

A unit rate is a comparison of any two separate but related quantities when they are combined into a single quantity. It is often expressed as a quantity per 1 unit.

To calculate the unit rate, divide the total cost by the number of items. For example, if 6 candles cost $15, the unit rate is $15 ÷ 6 = $2.50 per candle.

To find laps per minute, divide the total number of laps by the total time in minutes. For example, if Rosalie swims 8 laps in 5 minutes, it is 8 ÷ 5 = 1.6 laps per minute.

To calculate the percentage, divide the part by the whole and multiply by 100. For example, if 15 out of 25 children take the bus, the percentage is (15 ÷ 25) × 100 = 60%.

Speed is calculated by dividing the distance traveled by the time taken. For example, if you drive 360 miles in 6 hours, the speed is 360 ÷ 6 = 60 miles per hour.

To find the time taken, divide the distance by the speed. For example, if the speed is 60 miles per hour and the distance is 120 miles, the time is 120 ÷ 60 = 2 hours.

To find minutes per lap, divide the total time in minutes by the number of laps. For example, if it takes 5 minutes to swim 8 laps, it is 5 ÷ 8 = 0.625 minutes per lap.

Comparing unit rates helps determine which option is more cost-effective or efficient. For example, comparing the cost per candle from different stores.

A ratio is a relationship between two numbers indicating how many times the first number contains the second.

A ratio can be expressed as a fraction by placing the first number over the second number. For example, a ratio of 3:4 can be expressed as 3/4.