Eureka Lesson 8 and Zearn lesson 9 Flashcard

Front

What is a proportion?

Back

A proportion is an equation that states that two ratios are equal.

Front

How do you solve a proportion?

Back

To solve a proportion, cross-multiply the terms and then solve for the unknown variable.

Front

If a car travels 280 miles in 7 hours, what is its speed in miles per hour?

Back

Speed = Distance/Time = 280 miles / 7 hours = 40 miles per hour.

Front

What is the formula for direct variation?

Back

The formula for direct variation is y = kx, where k is the constant of variation.

Front

If a car travels at a constant speed, how far will it travel in 12 hours if it travels 40 miles per hour?

Back

Distance = Speed x Time = 40 miles/hour x 12 hours = 480 miles.

Front

Solve for w: 3w + 5 = 25

Back

w = (25 - 5) / 3 = 20 / 3 = 22/3.

Front

Solve for a: 12a - 5 = 107

Back

a = (107 + 5) / 12 = 112 / 12 = 107/12.

Front

What is the cross-multiplication method?

Back

The cross-multiplication method involves multiplying the numerator of one ratio by the denominator of the other ratio.

Front

What does it mean for two quantities to vary directly?

Back

Two quantities vary directly if one quantity increases, the other quantity increases proportionally.

Front

If 3/4 of a number is 12, what is the number?

Back

Let the number be x. Then, (3/4)x = 12, so x = 12 / (3/4) = 16.