Answer:
Here is your answer mate
Step-by-step explanation:
As we know that 7 person take 90 days so 1 person takes 90×7=630 days
As work has to be finished in 15 days than 630/15=42 so
42 people can complete work in 15 days but as we have already 7 people employed so required are
42-7=35 so 35 more are needed
