Question

The length and breadth of a playground are 62 m 60 cm and 25 m 40 cm respectively. Find the cost of turfing it at Rs 2.50 per square metre. How long will a man take to go three times round the field, if he walks at the rate of 2 metres per second.

Answer 1

We have,
Length of a playground = 62 m 60 cm = 62.6 m [ Since 10 cm = 0.1 m]
Breadth of a playground = 25 m 40 cm = 25.4 m
Area of a playground = Length x Breadth= 62.6 m x 25.4 m = 1590.04 m²
Rate of turfing = Rs. 2.50/m²
∴ Total cost of turfing = Rs. (1590.04 x 2.50) = Rs. 3975.10
Again,
Perimeter of a rectangular field = 2(Length + Breadth)
= 2(62.6 + 25.4) = 176 m
Distance covered by the man in 3 rounds of a field = 3 x Perimeter of a rectangular field
= 3 x 176 m = 528 m
The man walks at the rate of 2 m/sec.
or,
Rate = 2 x 60 m/min = 120 m/min
Thus,
Required time to cover a distance of 528 m = 528 m120 m/min=4.4 min
= 4 minutes 24 seconds [ since 0.1 minutes = 6 seconds]