a large tank can filled by a and b in 30 minutes and 45 minutes respectively . how many minutes will it take to fill the tanker from empty state if b is used for half the time and a and b fill it together for the other half ?
"part filled by a + b in 1 minute = 1 / 30 + 1 / 45 = 1 / 45 suppose the tank is filled in x minutes then , x / 2 ( 1 / 45 + 1 / 45 ) = 1 x / 2 * 2 / 45 = 1 x = 45 min answer is e"
multiply(divide(const_1, add(add(divide(const_1, 30), divide(const_1, 45)), divide(const_1, 45))), const_2)