A man travelled a distance of 61 km in 9 hours. He travelled partly on foot at 4 km/hr and partly on bicycle at 9 km/hr.
What is the distance travelled on foot?
12 km
14 km
16 km
18 km
Explanation:
Let the time in which he travelled on foot = x hr
Then the time in which he travelled on bicycle = (9−x) hr
distance = speed $ \times$ time
=> 4x + 9(9 − x) = 61
=> 4x + 81− 9x = 61
=> 5x = 20
=> x = 4
Distance travelled on foot = 4x = 4 $ \times$ 4 = 16 km
Let the time in which he travelled on foot = x hr
Then the time in which he travelled on bicycle = (9−x) hr
distance = speed $ \times$ time
=> 4x + 9(9 − x) = 61
=> 4x + 81− 9x = 61
=> 5x = 20
=> x = 4
Distance travelled on foot = 4x = 4 $ \times$ 4 = 16 km