Solve for x
x = \frac{15}{8} = 1\frac{7}{8} = 1.875
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15=15x\times \frac{1}{3}+15x\times \frac{1}{5}
Variable x cannot be equal to 0 since division by zero is not defined. Multiply both sides of the equation by 15x, the least common multiple of x,3,5.
15=\frac{15}{3}x+15x\times \frac{1}{5}
Multiply 15 and \frac{1}{3} to get \frac{15}{3}.
15=5x+15x\times \frac{1}{5}
Divide 15 by 3 to get 5.
15=5x+\frac{15}{5}x
Multiply 15 and \frac{1}{5} to get \frac{15}{5}.
15=5x+3x
Divide 15 by 5 to get 3.
15=8x
Combine 5x and 3x to get 8x.
8x=15
Swap sides so that all variable terms are on the left hand side.
x=\frac{15}{8}
Divide both sides by 8.
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