Subtract 75/27 from 28/70, Solve 28/70

Subtract 75/27 from 28/70

1^st number: 28/70, 2^nd number: 2 21/27

28/70 - 75/27 is -107/45.

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,
28/70 = 28 × 27/70 × 27 = 756/1890
Likewise, for the 2nd fraction, since 27 × 70 = 1890,
75/27 = 75 × 70/27 × 70 = 5250/1890
Subtract the two like fractions:
756/1890 - 5250/1890 = 756 - 5250/1890 = -4494/1890
After reducing the fraction, the answer is -107/45

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