Answer :
60x + 20y = 1440
x + y = 48
20x + 20y = 960
(60x - 20x) + (20y - 20y) = 1440 - 960
40x = 480
x = 12
x + y = 48
12 + y = 48
y = 48 - 12 = 36
x + y = 48
20x + 20y = 960
(60x - 20x) + (20y - 20y) = 1440 - 960
40x = 480
x = 12
x + y = 48
12 + y = 48
y = 48 - 12 = 36