Question

plz answer it.
Don't delete it. ​

Answer 1

Answer:

56.25%

Step-by-step explanation:

Given :-

Increase in diameter = 25%

Let the radius be "r" , diameter be "d" , initial CSA be "A" , increased CSA be A'

CSA of Sphere = 4πr²

Or as 2r = Diameter

CSA = πd² = A

Now diameter is increased by 25%

→ d + 0.25 d = 1.25d

Increased CSA = π × (1.25d)²

= π(1.5625)d² = A'

Now % increase

$= \dfrac{A' - A }{A} \times 100$

$= \dfrac{ \pi(1.5625)d^2 -\pi.d^2}{\pi.d^2} \times 100$

$= \dfrac{ 0.5625 \pi.d^2}{\pi.d^2} \times 100$

$= 56.25 \%$