Question

Kim can mow the greens at the golf course twice as fast as I can. Working together, we can mow them in 4 hours. How long will it take me to mow the greens alone?

Answer 1

Answer:

12 hours

Step-by-step explanation:

Let x hours be the time it will take you to mow the greens at the golf course.

Since Kim can mow twice as fast, it will take Kim x / 2 hours to mow the greens.

In 1 hour, you will mow 1 / x of the greens

in 1 hour, Kim will mow 1 / (x / 2) of the greens= 2 / x of the greens

In 4 hours, you will mow 4 * 1 / x of the course = 4 / x of the greens

In 4 hours, Kim will mow 4 * 1 / (x / 2) of the course = 4 / (x / 2) = 8 / x of the greens.

Since we are dealing in fraction, the sum of the amount of greens that they would individually mow in 4 hours should be 1. i.e

(4 / x) + (8 / x) = 1

12 / x = 1

Solve for x;

x = 12

Therefore, it will take you 12 hours to mow the greens alone.