Subtract 27/21 from 7/70, Solve 7/70

Subtract 27/21 from 7/70

1^st number: 7/70, 2^nd number: 1 6/21

7/70 - 27/21 is -83/70.

Find the least common denominator or LCM of the two denominators:
LCM of 70 and 21 is 210

Next, find the equivalent fraction of both fractional numbers with denominator 210
For the 1st fraction, since 70 × 3 = 210,
7/70 = 7 × 3/70 × 3 = 21/210
Likewise, for the 2nd fraction, since 21 × 10 = 210,
27/21 = 27 × 10/21 × 10 = 270/210
Subtract the two like fractions:
21/210 - 270/210 = 21 - 270/210 = -249/210
After reducing the fraction, the answer is -83/70

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