Answer:
B. 28 minutes
Step-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 garden
and
similarly, 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 minute
Solving the equation:
=
Garden weeded in one minute by both = 0.036
So, number of minutes to weed whole garden = 1/0.036
= 27.77 minutes
Rounding off will give us: 28 minutes
So,
Option B is the correct answer ..