Question

Carlos made $414 for 18 hours of work. At the same rate, how many hours would he have to work to make $299?

Answer 1

13 hours

Explanation:

This is indirect proportion.

A simple method to use is to multiply the second and third values and divide it by the first value.

If 18 hours =$414

x hours =$299

`414x = 18 * 299 \\ (414x)/(414) = (18 * 299)/(414)`

Cancelling out by 414 on the left side and by 3 on the right side

`x = (6 * 299)/(138)`

Note: We can only cancel numerators and denominators.

Cancelling out by 3

`x = (2 * 299)/(46) \\ cancelling \: again \: by \: 2 \\ x = (1 * 299)/(23)`

=>299/23 =13 hours

We have 13 hours as our answer.

Answer 2

13 hours

Explanation:

414 / 18 = 23

299 / 23 = 13