Question

the length of a rectangular field is 10m more than it's breadth. if its length is 50m, the find the time a boy takes to make two round of the field, if his speed is 1.5m per second. the answer in my book is 4 minutes​

Answer 1

Given :-

• The length of rectangular field = 50m
• The speed of the boy = 1.5m/s

To Find :-

• Time taken by the boy around the field = ?

Solution :-

• To calculate time taken by the boy , at first we have to find the breadth of rectangular field then calculate the distance covered by the boy. After that calculate the time with the help of formula.

As per the question the length of field is 10m more than breadth so, it means the breadth of field is 10m less then it's length

So,

⇢Breadth of field = 10m less then it's length

⇢Breadth of field = 50 - 10 = 40m

Now calculate distance covered by boy :-

⇢ Distance = 2times{Perimeter of filed}

⇢ Distance = 2{2(Length + breadth)}

⇢ Distance = 2{2(50 + 40)}

⇢ Distance = 2{2 × 90}

⇢ Distance = 2 × 180

⇢ Distance = 360m

Now calculate time taken by the boy :-

Here , Distance = 360m. Speed = 1.5m/s :-

⇢ Time = Distance / Speed

⇢ Time = 360/1.5

⇢ Time = 240 sec

⇢ Time = 240 ÷ 60 = 4 minutes

Therefore, Time taken by the boy is 4 minutes

Answer 2

QUESTION :-

the length of a rectangular field is 10m more than it's breadth. if its length is 50m, the find the time a boy takes to make two round of the field, if his speed is 1.5m per second. the answer in my book is 4 minutes

ANSWER :-

• time a boy takes = 4min

GIVEN :-

• the length of a rectangular field is 10m more than it's breadth. if its length is 50m

TO FIND :-

• find the time a boy takes to make two round of the field = ?

SOLUTION :-

it saying that 10 m less length

we have to minus 50 with 10 we get :-

= 50m - 10m = 40 m

we have to find How much distance covered :-

we have formula :-

Perimeter of rectangle = 2 { 2 L + b }

perimeter of rectangle = 2 { 50 + 40}

perimeter of rectangle = 2 { 2 × 90 }

perimeter of rectangle = 2 × 180

perimeter of rectangle = 360 m

then, we have how much boy taken

time :-

we have formula :-

T = D/S

taken time = 360/1.5

we will divide 360 with 1.5 we get :-

taken time by boy = 240

taken time by boy = 240/60

we will divide 240 with 60 we get :-

taken time by boy = 4 minutes

time a boy takes to make two round

of the field = 4 minutes