Question

21: A biker covered half the distance between two towns in 2 h 30 min. After that, he increased his speed by 2 km/h . He covered the second half of the distance in 2 h 20 min. Find the distance between the two towns and the initial speed of the biker.​

Answer 1

Step-by-step explanation:

Solution:

Let the initial speed of the biker be x km/h Increased speed of the bike will be (x+2)km/h

Time taken to cover half the distance

=2 h 30 min

=150 min

Time taken to cover the second half of the distance

=2 h 20 min

=140 min

We know that,

Distance= Speed × Time

We have,

$\sf\Rightarrow150 × x = 140(x + 2) \\ \sf\Rightarrow150x = 140x + 280 \\ \sf \:\Rightarrow150x-140x=280 \\ \sf \Rightarrow10x=280 \\ \sf \Rightarrow x= \frac{280}{10} =28$

Therefore, the initial speed of the biker is

28 km/h .

Distance between the towns = The total distance covered by the biker