Subtract 45/90 from 21/28
21/28 - 45/90 is 1/4.
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,
21/28 = 21 × 45/28 × 45 = 945/1260 - Likewise, for the 2nd fraction, since 90 × 14 = 1260,
45/90 = 45 × 14/90 × 14 = 630/1260 - Subtract the two like fractions:
945/1260 - 630/1260 = 945 - 630/1260 = 315/1260 - After reducing the fraction, the answer is 1/4
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