Subtract 30/28 from 21/90
1st number: 21/90, 2nd number: 1 2/28
21/90 - 30/28 is -88/105.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 90 and 28 is 1260
Next, find the equivalent fraction of both fractional numbers with denominator 1260 - For the 1st fraction, since 90 × 14 = 1260,
21/90 = 21 × 14/90 × 14 = 294/1260 - Likewise, for the 2nd fraction, since 28 × 45 = 1260,
30/28 = 30 × 45/28 × 45 = 1350/1260 - Subtract the two like fractions:
294/1260 - 1350/1260 = 294 - 1350/1260 = -1056/1260 - After reducing the fraction, the answer is -88/105
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