Subtract 21/56 from 7/45, Solve 7/45

Subtract 21/56 from 7/45

7/45 - 21/56 is -79/360.

Find the least common denominator or LCM of the two denominators:
LCM of 45 and 56 is 2520

Next, find the equivalent fraction of both fractional numbers with denominator 2520
For the 1st fraction, since 45 × 56 = 2520,
7/45 = 7 × 56/45 × 56 = 392/2520
Likewise, for the 2nd fraction, since 56 × 45 = 2520,
21/56 = 21 × 45/56 × 45 = 945/2520
Subtract the two like fractions:
392/2520 - 945/2520 = 392 - 945/2520 = -553/2520
After reducing the fraction, the answer is -79/360

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