Subtract 4/5 from 20/42
20/42 - 4/5 is -34/105.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 42 and 5 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 5 × 42 = 210,
4/5 = 4 × 42/5 × 42 = 168/210 - Subtract the two like fractions:
100/210 - 168/210 = 100 - 168/210 = -68/210 - After reducing the fraction, the answer is -34/105
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