Question

Any charming intelligent warm hearted and smart student help me to answer my question. ❤️​

Answer 1

My Answer-:

Let ra,rb be radius of A & B respectively  

Given S.A of B is 300% greater then S.A of A 

ans:87.5%

surface areas ratio:(r1/r2)^2=100/400 i.e r1/r2=1/2;

volumes ratio is:(r1/r2)^3=(1/2)^3=1/8

the percentage of A compared to B=(1/8)*100=12.5%

∴ Volume of A is 87.5% lower than B.

OR

Surface area of a sphere=4(pi)r^2

Since Surf. area of B=300% of surf. area of A

=> rad. of B=2.*rad. of A

Volume of sphere=4/3(pi)r^3

=>Vol. of B=8* Vol of A

=> Vol. of A is (1-1/8) times lower than Vol. of B

=>Vol of A=87.5% lower than Vol of B.

No(3)

ANS: K=700

EXP

4*PI*R^2=300*4*PI*r^2/100 + 4PI*r^2

=>R^2=4r^2

=>R/r=2

(4/3)PI*R^3=(4/3)PI*r^3[K/100+1]

=>(R/r)^3=[K/100+1]

=>8=[K/100+1]

=>K=700 ANS..