Q2 of 94 Page 45

Two boys can finish a work in 10 days when they work together. The first boy can do it alone in 15 days. Find in how many days will the second boy do it all himself?

If two boys work together they can finish a work in 10 days

Let the two boys be x & y


x & y’s 1-day work =


x + y = ..eq (1)


first boy (x) can do it in 15 days


x’s 1-day work =


x =


substituting the value of x in eq(1)


x + y =


+ y =


y =


y’s 1-day work =


so, second boy (y) can do a work in 30 days


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