Question

Eesha leaves home for school (which is a long distance away), riding her bicycle at a rate of kilometers per hour. Her mother discovers that she has not taken her maths homework fifteen minutes after Eesha has left. She immediately leaves home to take it to her by car. If her mother drives at 56 kilometers per hour, how far (in terms of kilometers) must she drive before she reaches Eesha?
3
4
2
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Answer 1

Answer:

2 km

Explanation:

Assuming Here that Esha ride bicycle at 7 km/Hr

Distance = Speed * Time

Distance Covered by Esha in 15 minutes = (15/60)*7 = 7/4 km

Let say Esha Mother Driver For T Mins before Catchig Esha

in T mins Distance covered by Esah = (T/60)*7 = 7T/60 km

Total Distance Covered by Esha = 7/4 + 7T/60  = (105 + 7T)/60

Distance Covered by Mother = (T/60)*56 = 56T/60

Both Distance should Be equal

(105 + 7T)/60 = 56T/60

=> 105 + 7T = 56T

=> 49T = 105

=> 7T = 15

=> T = 15/7

Distance Covered by Mother = 56 * (15/7) /60 =  2 km

Mother Must Drive 2 km before She reaches Esha