A car takes 2 hours to reach a destination by travelling at the speed of 60 km/h. How long will it take when the car travels at the speed of 80 km/h?

Solution:

Consider the speed to be x and the time taken to be y.

If the speed increases, the time required to reach will decrease. Hence, they are in inverse proportion.

Two numbers x and y are said to be in inverse proportion when an increase in one quantity decreases the other quantity and vice versa.

xy = k or x = (1/y) k

where k is a constant.

Hence, x₁y₁ = x₂y₂

60 × 2 = 80 × y₂

y₂ = (60 × 2)/80

y₂ = 3/2

y₂ = 1.5 hours

Thus, 1.5 hours are required to reach the destination if the speed is increased to 80 km/hour.

☛ Check: NCERT Solutions for Class 8 Maths Chapter 13

Video Solution:

A car takes 2 hours to reach a destination by travelling at the speed of 60 km/h. How long will it take when the car travels at the speed of 80 km/h?

Maths NCERT Solutions Class 8 Chapter 13 Exercise 13.2 Question 9

Summary:

A car takes 2 hours to reach a destination by travelling at the speed of 60 km/h. If the car travels at the speed of 80 km/h, it will reach its destination in 1.5 hours.

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