Question

X and Y together can construct a small quarantine center in 12 days, which X alone can construct in 30 days. In how long Y alone can construct it?​

Answer 1

X +Y = 12

X = 30

Y = ?

Y = 30 - 12

30 -12 =18

Answer 2

X+Y=12

SO, X=30

Y =?

:.30- 12=Y

=)18 =Y