two mechanics were working on your car . one can complete the given job in six hours , but the new guy takes 7 hours . they worked together for the first two hours , but then the first guy left to help another mechanic on a different job . how long will it take the new guy to finish your car ?
rate ( 1 ) = 1 / 6 rate ( 2 ) = 1 / 7 combined = 13 / 42 work done in 2 days = 13 / 21 work left = 8 / 21 rate * time = work left 1 / 8 * time = 8 / 21 time = 64 / 21 e
max(divide(subtract(const_1, multiply(add(divide(const_1, add(const_4, const_2)), divide(const_1, 7)), const_2)), divide(const_1, 7)), const_3)