Question
If Ankit drives a certain distance at 18 km/h, he gets
delayed by 3 hours. If he drives at 30 km/h, he reaches 2 hours before time. Find 40% of the distance travelled by Ankit.Solution
ATQ:
Let the distance travelled by Ankit = ‘d’ km
Let the usual time taken by Ankit to travel this distance = ‘t’ hours We have,
d ÷ 18 = t + 3…………………..(i)
Also, d ÷ 30 = t – 2…………………(ii) Equation (i) – Equation (ii), we get
(d/18) – (d/30) = t + 3 – (t – 2) = 5
Or, (5d – 3d) ÷ 90 = 5
So, d = (90 × 5) ÷ 2 = 225 So, 40% of the distance travelled by Ankit = 225 × 0.4 = 90 km
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