Subtract 40/28 from 21/30
1st number: 21/30, 2nd number: 1 12/28
21/30 - 40/28 is -51/70.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 30 and 28 is 420
Next, find the equivalent fraction of both fractional numbers with denominator 420 - For the 1st fraction, since 30 × 14 = 420,
21/30 = 21 × 14/30 × 14 = 294/420 - Likewise, for the 2nd fraction, since 28 × 15 = 420,
40/28 = 40 × 15/28 × 15 = 600/420 - Subtract the two like fractions:
294/420 - 600/420 = 294 - 600/420 = -306/420 - After reducing the fraction, the answer is -51/70
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