Question

a car covers 72km in 2 hours and a train covers 120km in 3 hour find the ratio of their speeds​

Answer 1

Step-by-step explanation:

the speed of car = 72/2 = 36km/h

the speed of train = 120/3 = 40km/h

ratio of their speeds = 36:40

= 9:10 (ans.)

HOPE IT'S HELP YOU...

Answer 2

Answer :-

The Required ratio is 9:10 .

Note:-

• Ratio is calculated of same quantities. For ex - we can calculate ratio of masses of two bodies in kg. But if one of them is in grams , we need to Convert it into kg or kg into g in order to find ratio.

• Distance , speed and time are realted to each other as ;

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

From these , we can deduce that ,

Speed can be founded as ,

$\boxed{\sf Speed=\dfrac{Distance}{time}}$

Time can be founded as ,

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

Explanation :-

Given that , a car covers 72km in 2 hours and a train covers 120km in 3 hour.

$\underline{\red{\sf Case\:1:-}}$

• Distance = 72km
• time = 2hr .

$\sf => Speed =\dfrac{s}{t}\\\\\sf=> Speed = \frac{72km}{2hr}\\\\=>\bf Speed_1 = 36kmhr^{-1}$

$\underline{\red{\sf Case\:2:-}}$

• Distance = 120 km
• time = 3 hr .

$\sf => Speed =\dfrac{s}{t}\\\\\sf=> Speed = \frac{120km}{3hr}\\\\=>\bf Speed_2 = 40kmhr^{-1}$

$\underline{\red{\sf Required\:Ratios:-}}$

$\sf=> S_1:S_2=36km/hr:40km/hr\\\\\sf =>\dfrac{S_1}{S_2}=\dfrac{36km/hr}{40km/hr}\\\\\bf => S_1:S_2= 9:10$