Question
If Sneha cycles a certain distance at 9 km/h, she
arrives 7 hours late. If she cycles at 15 km/h, she reaches 2 hours early. What is 80% of the distance Sneha covered?Solution
ATQ:
Let the distance travelled by Sneha = βdβ km
Let the usual time taken by Sneha to travel this distance = βtβ hours We have,
d Γ· 9 = t + 7β¦β¦β¦β¦β¦β¦β¦..(i)
Also, d Γ· 15 = t β 2β¦β¦β¦β¦β¦β¦β¦(ii) Equation (i) β Equation (ii), we get
(d/9) β (d/15) = t + 7 β (t β 2) = 9
Or, (5d β 3d) Γ· 45 = 9
So, d = (45 Γ 9) Γ· 2 = 202.5 So, 80% of the distance travelled by Sneha = 202.5 Γ 0.8 =Β 162 km
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