Question 386839
weight of cake A = x
weight of cake B = 15 - x
after purchase, 2x/3 of cake A remains, while 3(15-x)/4 of cake B remains.
From the given,{{{ 2x/3 = 3(15-x)/4 - 1/5}}}.Multiply both sides by 60, the LCD.
then {{{40x = 45(15 - x) - 12}}},
40x = 675 - 45x - 12,
85x = 663,
x = 7.8 kg, the weight of cake A, and
15 - x = 7.2 kg, the weight of cake B.