Subtract 21/27 from 45/75, Solve 45/75

Subtract 21/27 from 45/75

45/75 - 21/27 is -8/45.

Find the least common denominator or LCM of the two denominators:
LCM of 75 and 27 is 675

Next, find the equivalent fraction of both fractional numbers with denominator 675
For the 1st fraction, since 75 × 9 = 675,
45/75 = 45 × 9/75 × 9 = 405/675
Likewise, for the 2nd fraction, since 27 × 25 = 675,
21/27 = 21 × 25/27 × 25 = 525/675
Subtract the two like fractions:
405/675 - 525/675 = 405 - 525/675 = -120/675
After reducing the fraction, the answer is -8/45

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