Subtract 90/36 from 81/70, Solve 1 11/70

Subtract 90/36 from 81/70

1^st number: 1 11/70, 2^nd number: 2 18/36

81/70 - 90/36 is -47/35.

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,
81/70 = 81 × 18/70 × 18 = 1458/1260
Likewise, for the 2nd fraction, since 36 × 35 = 1260,
90/36 = 90 × 35/36 × 35 = 3150/1260
Subtract the two like fractions:
1458/1260 - 3150/1260 = 1458 - 3150/1260 = -1692/1260
After reducing the fraction, the answer is -47/35

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