The leanth and breadth of a playground are 80m and 35m respectively.
(i)-How long will a boy take to go three times round the field, if he walks at rate of 1.5m per second?
To calculate the time it will take for the boy to go three times around the field, we need to find the distance he will cover.
The distance around the field is equal to the perimeter of the playground.
Perimeter = 2(length + breadth)
Given:
Length = 80m
Breadth = 35m
Perimeter = 2(80 + 35) = 2(115) = 230m
Now, we can calculate the time using the formula:
Time = Distance / Speed
Given:
Distance = 3 times around the field = 3 * 230m = 690m
Speed = 1.5m/s
Time = 690m / 1.5m/s = 460 seconds
So, it will take the boy 460 seconds to go three times around the field.
To find out how long it will take for the boy to go three times around the field, we need to calculate the total distance he will cover in meters.
The perimeter of a rectangle is given by the formula 2(length + breadth). In this case, the length is 80m and the breadth is 35m.
Perimeter = 2(Length + Breadth)
Perimeter = 2(80m + 35m)
Perimeter = 2(115m)
Perimeter = 230m
Since the boy wants to go three times around the field, we need to multiply the perimeter by three.
Total Distance = 3 * Perimeter
Total Distance = 3 * 230m
Total Distance = 690m
Now that we know the total distance the boy needs to cover, we can calculate how long it will take him, given that he walks at a rate of 1.5m per second.
Time = Distance / Rate
Time = 690m / 1.5m/s
Time = 460 seconds
Therefore, the boy will take 460 seconds to go three times around the field if he walks at a rate of 1.5m per second.
how far is it three times around ?
Once you have that distance, and you know Time = Distance/rate
you can do it.
Perimeter= 2(l+b)
2(80+35)
115*2= 230
Distance covered in one round= 230 meteres
Distance covered in three rounds= 230*3
690 meteres
1/1000* 230
23/100
23/100* 60
69/5
13.8 minutes
800 seconds