Question

the length and breadth of playground are 80 metre and 30 metre respectively how long will a boy take to go three times round the field, if he walks at rate of 1.5 metre per second​

Answer 1

$\underline\bold{\huge{Solution !!}}$

$\bold{\large{Given:-}}$
Length of playground = 80 m

breadth of playground = 35 m

Speed = 1.5 m/sec.

Area of playground

= Length × breadth

= 80 × 35

= 2800 sq. m

i) Cost of levelling

= 4.5 × 2800

= 12600.0

= Rs. 12600

ii) perimeter of field

= 2 ( length + breadth)

= 2 ( 80 + 35 )

= 2 × 115

= 230 m

Distance covered by boy

= 3 × 230

= 690 m

speed = 1.5 m/sec.

Time = Distance / speed

= 690/1.5

= 460 sec.