Subtract 80/70 from 30/27, Solve 1 3/27

Subtract 80/70 from 30/27

1^st number: 1 3/27, 2^nd number: 1 10/70

30/27 - 80/70 is -2/63.

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

Next, find the equivalent fraction of both fractional numbers with denominator 1890
For the 1st fraction, since 27 × 70 = 1890,
30/27 = 30 × 70/27 × 70 = 2100/1890
Likewise, for the 2nd fraction, since 70 × 27 = 1890,
80/70 = 80 × 27/70 × 27 = 2160/1890
Subtract the two like fractions:
2100/1890 - 2160/1890 = 2100 - 2160/1890 = -60/1890
After reducing the fraction, the answer is -2/63

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