A person walks at a speed of 3 km/hr and reaches a destination in 7 hours. If the person increases the speed by 1 km/hr, how much earlier will they reach the destination

Correct option is C

Given:
Initial Speed (S1) = 3 km/hr
Time taken (T1) = 7 hours
Increase in speed = 1 km/hr
Formula Used:
Distance = Speed \times Time
New Time (T2) = $$\frac{\text{Distance}}{\text{New Speed}}$$​​
Solution:
Total Distance = 3 $$\times$$​ 7 = 21 km.
New Speed = 3 + 1 = 4 km/hr.
New Time (T2) = 21 / 4 = 5.25 hours.
Time saved (earlier) = 7 - 5.25 = 1.75 hours
So the correct answer is (c)