Subtract 2/15 from 21/42
21/42 - 2/15 is 11/30.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 42 and 15 is 210
Next, find the equivalent fraction of both fractional numbers with denominator 210 - For the 1st fraction, since 42 × 5 = 210,
21/42 = 21 × 5/42 × 5 = 105/210 - Likewise, for the 2nd fraction, since 15 × 14 = 210,
2/15 = 2 × 14/15 × 14 = 28/210 - Subtract the two like fractions:
105/210 - 28/210 = 105 - 28/210 = 77/210 - After reducing the fraction, the answer is 11/30
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