Q:

It takes William 45 minutes to weed the garden. It takes his younger sister May 75 minutes to do the same job. If they work together, how long will it take them?A. 25 minutesB. 28 minutesC. 36 minutesD. 60 minutes

Accepted Solution

A:
Answer:B. 28 minutesStep-by-step explanation:According to the given statement,William weeds the whole garden in 45 minutes, then in one minute he will weed 1/45 of the gardenandsimilarly, 1/75 of the garden in one minute. When they both will work together, they will weed (1/45+1/75) of the garden in one minuteSolving the equation:= [tex]\frac{1}{45}+ \frac{1}{75}\\= \frac{75+45}{3375}\\ =\frac{120}{3375}\\ = 0.036[/tex]Garden weeded in one minute by both = 0.036So, number of minutes to weed whole garden = 1/0.036= 27.77 minutesRounding off will give us: 28 minutesSo,Option B is the correct answer ..