Question

a rectangular park is 90 m long and 70 m broad . a man walks round it at the speed of 4km /hr what time will he take in making 5 rounds

Answer 1

Perimeter of park=2*160m =320m
Speed=4km/hr=4*5/18m/sec=10/9 m/sec
Time taken to walk 1 round =320/10/9
=320*9/10=288min
Time taken to walk 5 rounds =288*5=1440min
=24hrs

Hope it helps you

Answer 2

Answer: 24 Minutes

Explanation:

Given:

Length = 90m

Breadth = 70m

Rate of walking = 4km/hr

To find: In the given question, we have to find out the time taken by man for making 5 rounds.

Perimeter of rectangular field  = 2(length+breadth)

                                                  = 2(90+70)

                                                  = 2(160)

                                                  = 320

Therefore, Perimeter of rectangular field is 320m.

It is given that, Man walks at the rate of 4km/hr.

So, We have to convert it into km.

                           = 320/1000

                           = 0.320km

Time taken by person to walk 1 km = 4/60 (60 - Minutes)

Therefore, Distance travelled making

5 rounds = 5(0.320)

               = 1.6

Therefore, Distance travelled for making 5 rounds = 1.6 km.

We have to find time taken for making 5 rounds by person.

= 1.6 * 15 (Person needs 15 min for 1km)

= 24

Hence, Person takes 24 minutes for completing 5 rounds in rectangular field.