Subtract 90/21 from 27/40
1st number: 27/40, 2nd number: 4 6/21
27/40 - 90/21 is -1011/280.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 40 and 21 is 840
Next, find the equivalent fraction of both fractional numbers with denominator 840 - For the 1st fraction, since 40 × 21 = 840,
27/40 = 27 × 21/40 × 21 = 567/840 - Likewise, for the 2nd fraction, since 21 × 40 = 840,
90/21 = 90 × 40/21 × 40 = 3600/840 - Subtract the two like fractions:
567/840 - 3600/840 = 567 - 3600/840 = -3033/840 - After reducing the fraction, the answer is -1011/280
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