Răspuns:
25% × x = 4/5 × y
25/100 × X = 4/5 × y
1/4 × X = 4/5 × y
5 × x = 16 × y
x - 10 + y + 8 = 40
x + y - 2 = 40
x + y = 40 + 2
x + y = 42
x = 42 - y
5 × X = 16 × y
5 × (42 - y) = 16 × y
210 - 5 × y = 16 × y
210 = 16 × y + 5 × y
210 = 21 × y
y = 210 :21
y = 10
x = 42 - y
x = 42 - 10
x = 32