Subtract 40/45 from 21/28
21/28 - 40/45 is -5/36.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 28 and 45 is 1260
Next, find the equivalent fraction of both fractional numbers with denominator 1260 - For the 1st fraction, since 28 × 45 = 1260,
21/28 = 21 × 45/28 × 45 = 945/1260 - Likewise, for the 2nd fraction, since 45 × 28 = 1260,
40/45 = 40 × 28/45 × 28 = 1120/1260 - Subtract the two like fractions:
945/1260 - 1120/1260 = 945 - 1120/1260 = -175/1260 - After reducing the fraction, the answer is -5/36
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