Subtract 20/49 from 10/42, Solve 10/42

Subtract 20/49 from 10/42

10/42 - 20/49 is -25/147.

Find the least common denominator or LCM of the two denominators:
LCM of 42 and 49 is 294

Next, find the equivalent fraction of both fractional numbers with denominator 294
For the 1st fraction, since 42 × 7 = 294,
10/42 = 10 × 7/42 × 7 = 70/294
Likewise, for the 2nd fraction, since 49 × 6 = 294,
20/49 = 20 × 6/49 × 6 = 120/294
Subtract the two like fractions:
70/294 - 120/294 = 70 - 120/294 = -50/294
After reducing the fraction, the answer is -25/147

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