Symbiosis National Aptitude Test SNAP 2019 Paper

Value A fills bathtub in 10 hours
Value B fills bathtub in 15 hours
L.C.M. of 10 and 15 = 30
Work done by value A in 1 hour =

30

10

= 3 units
Work done by value B in 1 hour =

30

15

= 2 units
Let value B was open for t hours
then, 3 × 8 + 2 × t = 30
24 + 2t = 30
t = 3 hours
Hence, valve B was open for 3 hours.