Answer :
Answer:
r = 3.2
Step-by-step explanation:
If A varies inversely with the square of r, then A = kr^2
75 = k*4^2 = 16k
k = 75/16
Now A = (75/16)*r^2
48 = (75/16)*r^2
r^2 = 48(16/75) = 256/25
r = [tex]\sqrt{\frac{256}{25} }[/tex] = 16/5 = 3.2
Answer:
r = 3.2
Step-by-step explanation:
If A varies inversely with the square of r, then A = kr^2
75 = k*4^2 = 16k
k = 75/16
Now A = (75/16)*r^2
48 = (75/16)*r^2
r^2 = 48(16/75) = 256/25
r = [tex]\sqrt{\frac{256}{25} }[/tex] = 16/5 = 3.2