R varies jointly as S and the square of T. If R is 32.4 when S=0.2 and T=9, find R when S=0.5 and T=5. I believe the answer is R=25, could someone check this for me?

Answer 1

we have

R = k*S*T^2
32.4 = k*.2*9^2 = 16.2k
k=2

R = 2ST^2
R(.5,5) = 2*.5*25 = 25

Good job.

Answer 2

Thank you!!

Answer 3

Solution:
First, find the constant of variation "k",
R = kst^2
Substitute:
(32.4) = k (0.2)(9)^2
(32.4) = k (0.2)(81)
(32.4) = k (16.2)
k = 32.4/16.2
k = 2 - Constant of variation
Then, find R when S=0.5 and T=5
Solution:
R = kst^2
R = (2)(0.5)(5)^2
R = (2)(0.5)(25)
R = 25
Your answer is right bestie <3