Subtract 21/20 from 28/63
1st number: 28/63, 2nd number: 1 1/20
28/63 - 21/20 is -109/180.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 63 and 20 is 1260
Next, find the equivalent fraction of both fractional numbers with denominator 1260 - For the 1st fraction, since 63 × 20 = 1260,
28/63 = 28 × 20/63 × 20 = 560/1260 - Likewise, for the 2nd fraction, since 20 × 63 = 1260,
21/20 = 21 × 63/20 × 63 = 1323/1260 - Subtract the two like fractions:
560/1260 - 1323/1260 = 560 - 1323/1260 = -763/1260 - After reducing the fraction, the answer is -109/180
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