Rates, Ratios, Percentages

Front

What is a rate?

Back

A rate is a ratio that compares two different quantities, often expressed as a fraction or a decimal. For example, speed is a rate that compares distance to time.

Front

How do you calculate the unit price?

Back

To calculate the unit price, divide the total cost by the number of units purchased. For example, if 3 pizzas cost $4.50, the unit price is $4.50 ÷ 3 = $1.50 per pizza.

Front

What is a ratio?

Back

A ratio is a relationship between two numbers indicating how many times the first number contains the second. It can be expressed in various forms, such as a fraction, decimal, or with a colon.

Front

How do you convert minutes to seconds?

Back

To convert minutes to seconds, multiply the number of minutes by 60. For example, 18 minutes × 60 seconds/minute = 1,080 seconds.

Front

What does it mean to find a percentage of a number?

Back

Finding a percentage of a number involves calculating a portion of that number based on the percentage given. For example, to find 35% of 70, multiply 70 by 0.35.

Front

How do you calculate the original price after a discount?

Back

To find the original price after a discount, divide the sale price by (1 - discount rate). For example, if pillows cost $36 after a 25% discount, the original price is $36 ÷ (1 - 0.25) = $48.

Front

What is the formula for calculating percentage?

Back

The formula for calculating percentage is: (part/whole) × 100. For example, to find what percentage 50 is of 20, use (50/20) × 100 = 250%.

Front

How do you express a ratio in simplest form?

Back

To express a ratio in simplest form, divide both terms of the ratio by their greatest common divisor (GCD). For example, the ratio 4:8 can be simplified to 1:2.

Front

What is the relationship between rates and ratios?

Back

Rates are a specific type of ratio that compares two different units, while ratios can compare any two quantities, regardless of their units.

Front

How do you calculate a percentage increase?

Back

To calculate a percentage increase, subtract the original value from the new value, divide by the original value, and multiply by 100. For example, if a price increases from $50 to $60, the increase is (($60 - $50) / $50) × 100 = 20%.