Subtract 21/90 from 42/56
42/56 - 21/90 is 31/60.
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,
42/56 = 42 × 45/56 × 45 = 1890/2520 - Likewise, for the 2nd fraction, since 90 × 28 = 2520,
21/90 = 21 × 28/90 × 28 = 588/2520 - Subtract the two like fractions:
1890/2520 - 588/2520 = 1890 - 588/2520 = 1302/2520 - After reducing the fraction, the answer is 31/60
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