Question

A man takes 15 seconds move to make a complete revolution along the circumference
of a circular park than to cross the park along its diameter. If the speed of the man is
120 m per minute, find the area of the park.​

Answer 1

Step-by-step explanation:

Given,

• Time to cross along its diameter = t
• Time to make complete revolution along circumference = t+15

To find,

• radius of the park = ?
• area of the park = ?

We know,

• radius of a circle = d/2
• circumference of a circle = 2πr
• area of a circle = πr²

Let's first find the radius by using circumference :-

• circumference = 2πr
• t + 15 = 2 x 22/7 x t/2
• t + 15 = 22/7 x t
• t + 15 = 3.14 t
• 3.14 t - t = 15
• 2.14 t = 15
• t = 15/2.14
• t = 7seconds---------------1

Now we know the time,t and we have speed,s. let's find the distance :-

we know :- s = d/t

• 120meters/60seconds = d/7
• 120/60 = d/7
• 2 = d/7
• d = 14m---------------2

It has become complicated now. What is 'd' ? Is it radius or diameter or circumference ?

Let's see :-

We assumed the time to cross the diameter = t

We assumed the time to cross the diameter = tBut we found in equation(1) that t = 7s. So,

(1) that t = 7s. So,The distance can be calculated by :-

(1) that t = 7s. So,The distance can be calculated by :-given that s = 120/60 = 2m/s.

(1) that t = 7s. So,The distance can be calculated by :-given that s = 120/60 = 2m/s.If s = 2m/s then for 7s it is 7 x 2 = 14m.

(1) that t = 7s. So,The distance can be calculated by :-given that s = 120/60 = 2m/s.If s = 2m/s then for 7s it is 7 x 2 = 14m.So,the diameter is 14m.

(1) that t = 7s. So,The distance can be calculated by :-given that s = 120/60 = 2m/s.If s = 2m/s then for 7s it is 7 x 2 = 14m.So,the diameter is 14m.Radius = d/2 = 14/2 = 7m.

Now,it is time to find the area because we know the radius :-

• a = πr²
• a = 22/7 x 7 x 7
• a = 22 x 7
• a = 154m²

That was one logical question. Good ome mate. Sorry if there are any mistakes.

Hope it helps