Problem: a man is walking at a speed of 10 km per hour . after every kilometre , he takes rest for 6 minutes . how much time will be take to cover a distance of 6 kilometres ?
Rationale: "rest time = number of rest ã — time for each rest = 5 ã — 6 = 30 minutes total time to cover 6 km = ( 6 â  „ 10 ã — 60 ) minutes + 30 minutes = 66 minutes answer c"
annotated_formula: add(multiply(divide(6, 10), speed(const_60, const_1)), multiply(const_4, 6))