Subtract 20/30 from 20/42
20/42 - 20/30 is -4/21.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 42 and 30 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 30 × 7 = 210,
20/30 = 20 × 7/30 × 7 = 140/210 - Subtract the two like fractions:
100/210 - 140/210 = 100 - 140/210 = -40/210 - After reducing the fraction, the answer is -4/21
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