Subtract 30/42 from 21/28
21/28 - 30/42 is 1/28.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 28 and 42 is 84
Next, find the equivalent fraction of both fractional numbers with denominator 84 - For the 1st fraction, since 28 × 3 = 84,
21/28 = 21 × 3/28 × 3 = 63/84 - Likewise, for the 2nd fraction, since 42 × 2 = 84,
30/42 = 30 × 2/42 × 2 = 60/84 - Subtract the two like fractions:
63/84 - 60/84 = 63 - 60/84 = 3/84 - After reducing the fraction, the answer is 1/28
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