Răspuns:
a)
(x + 38/15) × 3/2 = 21/4
(x + 38/15) = 21/4 : 3/2
x + 38/15 = 21/4 × 2/3
x + 38/15 = 7/2
x = 7/2 - 38/15
x = (7×15 - 38×2)/30
x = (105-76)/30
x = 29/30
b)
y = 109/50 : 109/1000
y = 109/50 × 1000/109
y = 20