Subtract 21/28 from 10/45, Solve 10/45

Subtract 21/28 from 10/45

10/45 - 21/28 is -19/36.

Find the least common denominator or LCM of the two denominators:
LCM of 45 and 28 is 1260

Next, find the equivalent fraction of both fractional numbers with denominator 1260
For the 1st fraction, since 45 × 28 = 1260,
10/45 = 10 × 28/45 × 28 = 280/1260
Likewise, for the 2nd fraction, since 28 × 45 = 1260,
21/28 = 21 × 45/28 × 45 = 945/1260
Subtract the two like fractions:
280/1260 - 945/1260 = 280 - 945/1260 = -665/1260
After reducing the fraction, the answer is -19/36

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