Question

EXERCISE 11 A
1. A bus travels a distance of 186 km in 2 hours 35 minutes. What is the speed of the
in km/hr?
2. A train covers 35 km in 25 minutes. What is the speed of the train in km/hr?
3. A man walks 8 km in 1 hour 20 minutes. What is the speed of the man in km/h​

Answer 1

Answer :

• The speed of the bus is 72km/h.
• The speed of the train is 84km/h.
• The speed of the man is 6km/h.

Step-by-step explanation ::

1. A bus travels a distance of 186 km in 2 hours 35 minutes. What is the speed of the in km/hr ?

Solution :-

Given that,

• Distance covered by bus = 186km
• Time taken = 2 hours 35 minutes

As we know that,

$\bf{Speed = \dfrac{Distance}{Time}} \\ \\ \sf{Therefore,} \\ \\ \sf{\longmapsto \: \dfrac{186}{2 \: \dfrac{35}{60}}} \\ \\ \\ \sf{\longmapsto \: \dfrac{186}{2 \: \cancel{\dfrac{35}{60}}}} \\ \\ \\ \sf{\longmapsto \: \dfrac{186}{2 \: \dfrac{7}{12}}} \\ \\ \\ \sf{\longmapsto \: \dfrac{186}{\dfrac{31}{12}}} \\ \\ \\ \sf{\longmapsto \: \dfrac{186 \times 12}{31}} \\ \\ \\ \sf{\longmapsto \: \dfrac{2232}{31}} \\ \\ \\ \sf{\longmapsto \: \ \cancel{ \dfrac{2232}{31}}} \\ \\ \\ \bf{\longmapsto \: 72}$

• The speed of the bus is 72km/h.

2. A train covers 35 km in 25 minutes. What is the speed of the train in km/hr ?

Solution :-

Given that,

• Distance covered by train = 35km
• Time taken = 25 minutes

As we know that,

$\bf{Speed = \dfrac{Distance}{Time}} \\ \\ \sf{Therefore,} \\ \\ \sf{\longmapsto \: \dfrac{35}{\dfrac{25}{60}}} \\ \\ \\ \sf{\longmapsto \: \dfrac{35 \times 60}{25}} \\ \\ \\ \sf{\longmapsto \: \dfrac{2100}{25}} \\ \\ \\ \sf{\longmapsto \: \ \cancel{ \dfrac{2100}{25}}} \\ \\ \\ \bf{\longmapsto \: 84}$

• The speed of the train is 84km/h.

3. A man walks 8 km in 1 hour 20 minutes. What is the speed of the man in km/h ?

Solution :-

Given that,

• Distance covered by man = 8km
• Time taken = 1 hour 20 minutes

As we know that,

$\bf{Speed = \dfrac{Distance}{Time}} \\ \\ \sf{Therefore,} \\ \\ \sf{\longmapsto \: \dfrac{8}{1 \: \dfrac{20}{60}}} \\ \\ \\ \sf{\longmapsto \: \dfrac{8}{1 \: \cancel{\dfrac{20}{60}}}} \\ \\ \\ \sf{\longmapsto \: \dfrac{8}{1\: \dfrac{1}{3}}} \\ \\ \\ \sf{\longmapsto \: \dfrac{8}{\dfrac{4}{3}}} \\ \\ \\ \sf{\longmapsto \: \dfrac{8 \times 3}{4}} \\ \\ \\ \sf{\longmapsto \: \dfrac{24}{4}} \\ \\ \\ \sf{\longmapsto \: \ \cancel{ \dfrac{24}{4}}} \\ \\ \\ \bf{\longmapsto \: 6}$

• The speed of the man is 6km/h.