Subtract 45/21 from 27/40, Solve 27/40

Subtract 45/21 from 27/40

1^st number: 27/40, 2^nd number: 2 3/21

27/40 - 45/21 is -411/280.

Find the least common denominator or LCM of the two denominators:
LCM of 40 and 21 is 840

Next, find the equivalent fraction of both fractional numbers with denominator 840
For the 1st fraction, since 40 × 21 = 840,
27/40 = 27 × 21/40 × 21 = 567/840
Likewise, for the 2nd fraction, since 21 × 40 = 840,
45/21 = 45 × 40/21 × 40 = 1800/840
Subtract the two like fractions:
567/840 - 1800/840 = 567 - 1800/840 = -1233/840
After reducing the fraction, the answer is -411/280

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