Subtract 49/36 from 90/70, Solve 1 20/70

Subtract 49/36 from 90/70

1^st number: 1 20/70, 2^nd number: 1 13/36

90/70 - 49/36 is -19/252.

Find the least common denominator or LCM of the two denominators:
LCM of 70 and 36 is 1260

Next, find the equivalent fraction of both fractional numbers with denominator 1260
For the 1st fraction, since 70 × 18 = 1260,
90/70 = 90 × 18/70 × 18 = 1620/1260
Likewise, for the 2nd fraction, since 36 × 35 = 1260,
49/36 = 49 × 35/36 × 35 = 1715/1260
Subtract the two like fractions:
1620/1260 - 1715/1260 = 1620 - 1715/1260 = -95/1260
After reducing the fraction, the answer is -19/252

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