Subtract 21/28 from 30/45
30/45 - 21/28 is -1/12.
Steps for subtracting fractions
- 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,
30/45 = 30 × 28/45 × 28 = 840/1260 - Likewise, for the 2nd fraction, since 28 × 45 = 1260,
21/28 = 21 × 45/28 × 45 = 945/1260 - Subtract the two like fractions:
840/1260 - 945/1260 = 840 - 945/1260 = -105/1260 - After reducing the fraction, the answer is -1/12
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