Subtract 81/21 from 20/50
1st number: 20/50, 2nd number: 3 18/21
20/50 - 81/21 is -121/35.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 50 and 21 is 1050
Next, find the equivalent fraction of both fractional numbers with denominator 1050 - For the 1st fraction, since 50 × 21 = 1050,
20/50 = 20 × 21/50 × 21 = 420/1050 - Likewise, for the 2nd fraction, since 21 × 50 = 1050,
81/21 = 81 × 50/21 × 50 = 4050/1050 - Subtract the two like fractions:
420/1050 - 4050/1050 = 420 - 4050/1050 = -3630/1050 - After reducing the fraction, the answer is -121/35
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