Subtract 2/28 from 21/42
21/42 - 2/28 is 3/7.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 42 and 28 is 84
Next, find the equivalent fraction of both fractional numbers with denominator 84 - For the 1st fraction, since 42 × 2 = 84,
21/42 = 21 × 2/42 × 2 = 42/84 - Likewise, for the 2nd fraction, since 28 × 3 = 84,
2/28 = 2 × 3/28 × 3 = 6/84 - Subtract the two like fractions:
42/84 - 6/84 = 42 - 6/84 = 36/84 - After reducing the fraction, the answer is 3/7
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