Question

The length and breadth of a playground are 80 m and 35 m respectively.
(1) Find the cost of levelling it at 450 per square metre.
(i) How long will a boy take to go three times round the field, if he walks at rate of 1.5 m per second ?
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Answer 1

Step-by-step explanation:

1. area of playground = 35m *80m = 2800 square metre

so, cost of leveling = 2800 square metre *450 square metre = Rs1260000

2. perimeter of playground = 2 ( 80+35) = 2*115 = 230

so, time taken for one round = 230/1.5 = 154 sec

so, total time = 3*154 = 462 sec = 7 min 42 sec