Question

1. A and B together can complete a piece of work in 12 |
days, B and C can do it in 20 days and C and A can
do it in 15 days. A, B and C together can complete
it in
a) 6 days b) 8 days c) 10 days d) 12 days​

Answer 1

Answer:

(D) 12days

Step-by-step explanation:

A+B = 12.........(eq-1)

B+C = 20........(eq-2)

A+C = 15.........(eq-3)

Eq(3) - Eq(1)=

C-B = 3......(Eq-4)

Eq(4) + Eq(2) =

C=23

By putting value of C in eq.3 ............. [A=(-8)]

By putting value of C in Eq.2.........…. [B= (-3)]

So, A+B+C = (-8)+(-3)+23 = 12days