Evaluate
\frac{6k}{7}+\frac{9j}{10}
Factor
\frac{3\left(21j+20k\right)}{70}
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\frac{7\times 9j}{70}+\frac{10\times 6k}{70}
To add or subtract expressions, expand them to make their denominators the same. Least common multiple of 10 and 7 is 70. Multiply \frac{9j}{10} times \frac{7}{7}. Multiply \frac{6k}{7} times \frac{10}{10}.
\frac{7\times 9j+10\times 6k}{70}
Since \frac{7\times 9j}{70} and \frac{10\times 6k}{70} have the same denominator, add them by adding their numerators.
\frac{63j+60k}{70}
Do the multiplications in 7\times 9j+10\times 6k.
\frac{3\left(21j+20k\right)}{70}
Factor out \frac{3}{70}.
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