Solve the equation: 2x of 3 + 3x of 5 = 7 of 20

Solve the equation: 2x of 3 + 3x of 5 = 7 of 20

2X out of 3 + 3x out of 5 is 19x out of 15
19x of 15 = 7 of 20
X = 21 / 76