Answer:
x = 112
Explanation:
Given that y varies directly as x then the equation relating them is
y = kx ← k is the constant of variation
To find k use the condition y = 35 when x = 140, then
35 = 140k ( divide both sides by 140 )
0.25 = k
y = 0.25x ← equation of variation
When y = 28, then
28 = 0.25x ( divide both sides by 0.25 )
x = 112