Subtract 90/21 from 27/10, Solve 2 7/10

Subtract 90/21 from 27/10

1^st number: 2 7/10, 2^nd number: 4 6/21

27/10 - 90/21 is -111/70.

Find the least common denominator or LCM of the two denominators:
LCM of 10 and 21 is 210

Next, find the equivalent fraction of both fractional numbers with denominator 210
For the 1st fraction, since 10 × 21 = 210,
27/10 = 27 × 21/10 × 21 = 567/210
Likewise, for the 2nd fraction, since 21 × 10 = 210,
90/21 = 90 × 10/21 × 10 = 900/210
Subtract the two like fractions:
567/210 - 900/210 = 567 - 900/210 = -333/210
After reducing the fraction, the answer is -111/70

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