Exercise 12 (A) Question 10 - Selina Mathematic Class 6 – Idea of Speed, Distance & Time.

Problem 10: The speed of sound in air is about 330ms−1. Express this speed in kmh−1. How long will the sound take to travel 99 km?

Selina concise maths solution by Manoj Agarwal,

Exercise 12 (A) Question 10, Selina Mathematic Class 6, Idea of Speed, Distance & Time,

Problem 10: The speed of sound in air is about 330ms−1, Express this speed in kmh−1, How long will the sound take to travel 99 km, 

Solution

Given

Speed of sound in air =330m/sec

So, speed =330m/sec

Distance=99km

=99×1000

We get,

=99000m

Hence,

Time=[(99000m)/(330m/sec)]

=9900/33sec

We get,

=300sec

=5min

Hence, the time is taken by the sound to travel 99 km in 5 min