Subtract 21/90 from 2/28
2/28 - 21/90 is -17/105.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 28 and 90 is 1260
Next, find the equivalent fraction of both fractional numbers with denominator 1260 - For the 1st fraction, since 28 × 45 = 1260,
2/28 = 2 × 45/28 × 45 = 90/1260 - Likewise, for the 2nd fraction, since 90 × 14 = 1260,
21/90 = 21 × 14/90 × 14 = 294/1260 - Subtract the two like fractions:
90/1260 - 294/1260 = 90 - 294/1260 = -204/1260 - After reducing the fraction, the answer is -17/105
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