Subtract 20/42 from 15/35
15/35 - 20/42 is -1/21.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 35 and 42 is 210
Next, find the equivalent fraction of both fractional numbers with denominator 210 - For the 1st fraction, since 35 × 6 = 210,
15/35 = 15 × 6/35 × 6 = 90/210 - Likewise, for the 2nd fraction, since 42 × 5 = 210,
20/42 = 20 × 5/42 × 5 = 100/210 - Subtract the two like fractions:
90/210 - 100/210 = 90 - 100/210 = -10/210 - After reducing the fraction, the answer is -1/21
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