Subtract 1/90 from 21/56
21/56 - 1/90 is 131/360.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 56 and 90 is 2520
Next, find the equivalent fraction of both fractional numbers with denominator 2520 - For the 1st fraction, since 56 × 45 = 2520,
21/56 = 21 × 45/56 × 45 = 945/2520 - Likewise, for the 2nd fraction, since 90 × 28 = 2520,
1/90 = 1 × 28/90 × 28 = 28/2520 - Subtract the two like fractions:
945/2520 - 28/2520 = 945 - 28/2520 = 917/2520 - After reducing the fraction, the answer is 131/360
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