Subtract 15/40 from 90/21
1st number: 4 6/21, 2nd number: 15/40
90/21 - 15/40 is 219/56.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 40 is 840
Next, find the equivalent fraction of both fractional numbers with denominator 840 - For the 1st fraction, since 21 × 40 = 840,
90/21 = 90 × 40/21 × 40 = 3600/840 - Likewise, for the 2nd fraction, since 40 × 21 = 840,
15/40 = 15 × 21/40 × 21 = 315/840 - Subtract the two like fractions:
3600/840 - 315/840 = 3600 - 315/840 = 3285/840 - After reducing the fraction, the answer is 219/56
- In mixed form: 351/56
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