Zakir travels from City A to City B. If Zakir drives his car at $$\frac38$$​ of his normal speed, then he reaches City B 45 minutes late. Find the time (in minutes) that Zakir would have taken to travel from City A to City B if he drove at his normal speed.

Correct option is D

Given:

When Zakir drives at $$\frac{3}{8}$$​ of his normal speed, he is 45 minutes late.

We are to find the time (in minutes) Zakir would take at normal speed.

Formula Used:

Speed = $$\frac{distance}{time}$$​​

Solution:

Let normal time = t minutes

At reduced speed $$\frac{3}{8}$$​, time taken becomes $$\frac{8}{3} \times t$$​​

So, extra time = $$\frac{8}{3}t - t = \frac{5}{3}t$$​​

From the condition; $$\frac{5}{3}t = 45$$​​

​$$\frac{5}{3}t = 45$$​​

$$t = \frac{45 \times 3}{5}$$​ = 27 minutes

Alternate Solution:

Distance is constant, so;

Speed $$\propto \frac{1}{time}$$​​

Speed changes - 8 : 3

Time changes - 3 : 8

Extra time = 45 min.

(8 – 3) unit = 45 min

5 unit = 45 min

1 unit = 9 min

Total time with normal speed = 3 × 9 = 27 min