Subtract 1/40 from 21/27, Solve 21/27

Subtract 1/40 from 21/27

21/27 - 1/40 is 271/360.

Find the least common denominator or LCM of the two denominators:
LCM of 27 and 40 is 1080

Next, find the equivalent fraction of both fractional numbers with denominator 1080
For the 1st fraction, since 27 × 40 = 1080,
21/27 = 21 × 40/27 × 40 = 840/1080
Likewise, for the 2nd fraction, since 40 × 27 = 1080,
1/40 = 1 × 27/40 × 27 = 27/1080
Subtract the two like fractions:
840/1080 - 27/1080 = 840 - 27/1080 = 813/1080
After reducing the fraction, the answer is 271/360

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