Subtract 3/15 from 20/42
20/42 - 3/15 is 29/105.
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,
20/42 = 20 × 5/42 × 5 = 100/210 - Likewise, for the 2nd fraction, since 15 × 14 = 210,
3/15 = 3 × 14/15 × 14 = 42/210 - Subtract the two like fractions:
100/210 - 42/210 = 100 - 42/210 = 58/210 - After reducing the fraction, the answer is 29/105
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