Question

A man travelled a distance of 61 km in 9 hours partly on foot at the rate of 4 kilometre per hour and partly on bicycle at the rate of 9 kilometre per hour the distance travelled on foot was

Answer 1

$\sf{\underline{Answer:}}$ 16 km

$\sf{\underline{Given:}}$

Total distance = 61 km

$\sf{\underline{Now:}}$

Let the time in which he travelled on foot be a hour.

Time for travelling on bicycle be (9 - a) hr.

$\sf{\underline{We\:know\:that:}}$

$\boxed{\sf{Distance = Speed \times Time}}$

$\sf{\underline{So:}}$

$\implies$ $\sf{4a + 9(9 - a) = 61}$

$\implies$ $\sf{4a + 81 - 9a = 61}$

$\implies$ $\sf{4a - 9a = 61 - 81}$

$\implies$ $\sf{- 5a = - 20}$

$\implies$ $\sf{a = \frac{ - 20}{ - 5}}$

$\implies$ $\sf{a = 4}$

$\sf{\underline{Therefore:}}$

Distance traveled on foot $\sf{4(4) = 16 \: km.}$

Answer 2

Answer:

The distance traveled on foot was 16 km

Step-by-step explanation:

Total distance = 61 km

total time = 9 hours

Let the time taken by travelling on foot be x

So,  the time taken by travelling on bicycle = 9- x

Speed on foot = 4 km/hr

Speed on bicycle= 9 km/hr

$Distance =  Speed \times Time$

Distance traveled by foot= 4x

Distance traveled by bicycle = 9(9-x)

ATQ

$4x +9(9 - x) = 61$

$4x +81- 9x= 61$

 $81- 5x= 61$

 $5x= 20$

 $x= 4$

Distance traveled by foot= 4x = 4 * 4 = 16 km

Hence the distance traveled on foot was 16 km