Subtract 81/21 from 40/20
1st number: 2 0/20, 2nd number: 3 18/21
40/20 - 81/21 is -13/7.
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,
40/20 = 40 × 21/20 × 21 = 840/420 - Likewise, for the 2nd fraction, since 21 × 20 = 420,
81/21 = 81 × 20/21 × 20 = 1620/420 - Subtract the two like fractions:
840/420 - 1620/420 = 840 - 1620/420 = -780/420 - After reducing the fraction, the answer is -13/7
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