If pipe 'A' can fill \(\frac{1}{3}\) part of a tank in 2 hours and 'B' can fill \(\frac{1}{8}\) part of the tank in 1 hour. In how many time they can fill 33.33% of the tank by working together?
Answer & explanation
Correct answer: option 3
A can fill \(\frac{1}{3}\) of tank in = 2 h
⇒ A can fill complete tank in = 6 h and
B can fill \(\frac{1}{8}\) of tank in = 1 h
⇒ B can fill complete tank in = 8 h
Now, let total capacity of the tank = 24 ltr.

Efficiency of A = 4 lt/hr
Efficiency of B = 3 lt/hr
Hence,
\(\frac{1}{3}\) of the tank will be filled in = \(\frac{24}{4+3}\) × \(\frac{1}{3}\) = \(\frac{24}{21}\) = \(\frac{8}{7}\)