Subtract 21/90 from 5/28
5/28 - 21/90 is -23/420.
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,
5/28 = 5 × 45/28 × 45 = 225/1260 - Likewise, for the 2nd fraction, since 90 × 14 = 1260,
21/90 = 21 × 14/90 × 14 = 294/1260 - Subtract the two like fractions:
225/1260 - 294/1260 = 225 - 294/1260 = -69/1260 - After reducing the fraction, the answer is -23/420
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