Subtract 42/21 from 8/20
1st number: 8/20, 2nd number: 2 0/21
8/20 - 42/21 is -8/5.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 20 and 21 is 420
Next, find the equivalent fraction of both fractional numbers with denominator 420 - For the 1st fraction, since 20 × 21 = 420,
8/20 = 8 × 21/20 × 21 = 168/420 - Likewise, for the 2nd fraction, since 21 × 20 = 420,
42/21 = 42 × 20/21 × 20 = 840/420 - Subtract the two like fractions:
168/420 - 840/420 = 168 - 840/420 = -672/420 - After reducing the fraction, the answer is -8/5
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