state gov Bihar SSC (BSSC) Inter Level Mock Test 2024 - 25 Quantitative Aptitude Time and Work Pipe and Cistern
A tank has two pipes. Pipe M is for filling the tank and pipe N is for emptying the tank. If pipe M takes 45 hours to completely fill the tank and pipe N takes 90 hours to empty the fully filled tank, then how many hours will they take to together fill the half empty tank completely?
1
35 hours
2
40 hours
3
45 hours
4
60 hours