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# Mukesh walks around a circular track of radius 14 m with a speed of 4 km/hr. If he takes 20 rounds of the track, for how long does he walk?

**Solution:**

The__ circumference __of the track = Circumference of the circle of radius r = 2πr

Where r = radius of the track = 14m

The distance walked by Mukesh is = 20 × (Circumference of the Track)

Circumference of the track = 2 × (22/7) × 14 [π = 22/7]

Circumference of the track = 88 m

Since Mukesh takes 20 rounds it means:

Distance Travelled by Mukesh = 20 × 88 = 1760 m = 1.76 km

Time taken by Mukesh to Cover 1.76 km = 1.76/4 = 0.44 hours = 26.40 minutes

Hence Mukesh walks 26.40 minutes.

**✦ Try This:** Mukesh runs around a circular track of radius 28 m with a speed of 8 km/hr. If he takes 25 rounds of the track, for how long does he run?

The circumference of the track = Circumference of the circle of radius r = 2πr

Where r = radius of the track = 28m

The distance walked by Mukesh is = 20 × (Circumference of the Track)

Circumference of the track = 2 × (22/7) × 28 [π = 22/7]

Circumference of the track = 704 m

Since Mukesh takes 25 rounds it means:

Distance Travelled by Mukesh = 25 × 704 = 17600 m = 17.60 km

Time taken by Mukesh to Cover 17.60 km = 17.6/8 = 2.2 hours = 2 hours 12 minutes

Hence Mukesh runs for 2 hours 12 minutes.

**☛ Also Check: **NCERT Solutions for Class 8 Maths Chapter 11

**NCERT Exemplar Class 8 Maths Chapter 11 Problem 68**

## Mukesh walks around a circular track of radius 14 m with a speed of 4 km/hr. If he takes 20 rounds of the track, for how long does he walk?

**Summary:**

Mukesh walks around a circular track of radius 14 m with a speed of 4 km/hr. If he takes 20 rounds of the track, he walks for 26.40 minutes

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