Question

50 labourers can dig a pond in 16 days. How
many labourers will be required to dig another
pond, double in size, in 20 days?​

Answer 1

50 labourers can dig a pond in 16 days.

16×2=32. (because the size of pond is doubled)

16 labourers can dig pond in 32 days.

so how many labourers can dig that pond in 20 days.

Days are decreased , labourers will increase .

they are inversely proportional to each other .

x×y=k

32×20=16×x

x=32×20/16

x=640/16

x=40