Subtract 21/7 from 8/20
1st number: 8/20, 2nd number: 3 0/7
8/20 - 21/7 is -13/5.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 20 and 7 is 140
Next, find the equivalent fraction of both fractional numbers with denominator 140 - For the 1st fraction, since 20 × 7 = 140,
8/20 = 8 × 7/20 × 7 = 56/140 - Likewise, for the 2nd fraction, since 7 × 20 = 140,
21/7 = 21 × 20/7 × 20 = 420/140 - Subtract the two like fractions:
56/140 - 420/140 = 56 - 420/140 = -364/140 - After reducing the fraction, the answer is -13/5
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