Direct Variation

Front

What is Direct Variation?

Back

Direct Variation is a relationship between two variables where one variable is a constant multiple of the other. It can be expressed as y = kx, where k is a non-zero constant.

Front

If y = 39 when x = 3, what is the constant of variation (k)?

Back

k = y/x = 39/3 = 13.

Front

In a direct variation, if x is halved, what happens to y?

Back

y is also halved.

Front

If $70.00 is earned in 5 hours, how much is earned per hour?

Back

$14.00 per hour.

Front

If Shawn earns $123.00 for 20 hours of work, how much will he earn for 31 hours?

Back

$190.65.

Front

What is the formula to find the amount earned in direct variation?

Back

Amount Earned = (Rate per Hour) x (Number of Hours Worked).

Front

How do you find the unit rate from a total cost?

Back

Divide the total cost by the total quantity to find the cost per unit.

Front

If Trina earns $187.15 for 19 hours, how much will she earn for 40 hours?

Back

$394.00.

Front

What does it mean if two quantities vary directly?

Back

It means that as one quantity increases, the other quantity increases at a constant rate.

Front

If y varies directly with x and y = 26 when x = 2, what is the value of y when x = 4?

Back

y = 52.