A rectangular field is 90m by 70m . A man walks round it at the rate of 4km/hr what time will he take in making 5 rounds .............. plzz help me guys Monday is my examination plzz ...
Answers
rate of walking = 4 km/hr = 4 × 1000 ÷ 3600
= 10/9 m/sec
no. of rounds = 5
time taken to complete 5 rounds of field =
= 320 × 5 ÷ 10/9
= 1440 sec
= 24 minutes
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.