Subtract 35/27 from 21/70, Solve 21/70

Subtract 35/27 from 21/70

1^st number: 21/70, 2^nd number: 1 8/27

21/70 - 35/27 is -269/270.

Find the least common denominator or LCM of the two denominators:
LCM of 70 and 27 is 1890

Next, find the equivalent fraction of both fractional numbers with denominator 1890
For the 1st fraction, since 70 × 27 = 1890,
21/70 = 21 × 27/70 × 27 = 567/1890
Likewise, for the 2nd fraction, since 27 × 70 = 1890,
35/27 = 35 × 70/27 × 70 = 2450/1890
Subtract the two like fractions:
567/1890 - 2450/1890 = 567 - 2450/1890 = -1883/1890
After reducing the fraction, the answer is -269/270

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