Question

19. The area of a square field is 60025 m? A man cycles along its boundary at 18 km/h. In ho
much time will he return to the starting point?​

Answer 1

Given :-

• Area of a square field is 60025 m

• Boundary is 18 km/h

To find :-

• How much time will he return to the starting point ?

Solution :-

The area of square field = 60025 m²

Speed of cyclist = 18 km/h

= 18 × ( 1000/60×60 )

= 5 m/s²

Area = 60025 m²

Side2 = 60025

Side = √60025

= 245

Formula : Area of square = 4 × side

Total length of boundary = 4 × Side

= 4 × 245 = 980 m

Now ,

Time taken to return to the starting point :-

= 980/5 = 196 seconds

★ 3 minutes 16 seconds

So, the final answer is 3 minutes 16 Seconds.

Answer 2

Given

• The area of a square field is 60025 m
• A man cycles along its boundary at 18 km/h

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To Find

• The time he will return to the starting point.

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Solution

First, we need to find the perimeter of the square field. To do so, we will use the value of the given area to find the value of the side and use it to find the perimeter of the square field.

Formula to find the Area of Square → (Side)²

Formula to find the Side of Square with Given Area → √(Area of Square)

Side of Square Field → √60025

Side of Square Field → 245 m

∴ The measure of the side of the square field is 245 m.

Perimeter of Square → 4 × (Side)

Perimeter of Square Field → 4 × 245

Perimeter of Square Field → 980 m

∴ The perimeter of the square field is 980 m.

Let's convert the speed from km/h to m/s first.

Speed → 18 km/h

Speed → $\dfrac{18}{1}\times \dfrac{1000}{3600}$

Speed → $\dfrac{18000}{3600}$

Speed → 5 m/s

∴ 18 km/h = 5 m/s

Speed = $\sf \dfrac{Distance}{Time}$

Speed of Man → 5 m/s

Distance Travelled by Man → 980 m

Time Taken → x

Time Taken = $\sf \dfrac{Distance}{Speed}$

Time Taken → $\dfrac{980}{5}$

Time Taken → 196 sec

∴ He will return to the starting point after 196 seconds.

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