Answer:
see explanation
Step-by-step explanation:
let m be mars and e be earth.
Given that m varies directly with e then the equation relating them is
m = ke ← k is the constant of variation
To find k use the condition m = 50, e = 150, then
k = [tex]\frac{m}{e}[/tex] = [tex]\frac{50}{150}[/tex] = [tex]\frac{1}{3}[/tex]
m = [tex]\frac{1}{3}[/tex] e ← equation of variation
When e = 120, then
m = [tex]\frac{1}{3}[/tex] × 120 = 40 pounds
