Answer:
12 hours
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.