Subtract 70/90 from 42/49, Solve 42/49

Subtract 70/90 from 42/49

42/49 - 70/90 is 5/63.

Find the least common denominator or LCM of the two denominators:
LCM of 49 and 90 is 4410

Next, find the equivalent fraction of both fractional numbers with denominator 4410
For the 1st fraction, since 49 × 90 = 4410,
42/49 = 42 × 90/49 × 90 = 3780/4410
Likewise, for the 2nd fraction, since 90 × 49 = 4410,
70/90 = 70 × 49/90 × 49 = 3430/4410
Subtract the two like fractions:
3780/4410 - 3430/4410 = 3780 - 3430/4410 = 350/4410
After reducing the fraction, the answer is 5/63

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