Subtract 81/16 from 21/45
1st number: 21/45, 2nd number: 5 1/16
21/45 - 81/16 is -1103/240.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 45 and 16 is 720
Next, find the equivalent fraction of both fractional numbers with denominator 720 - For the 1st fraction, since 45 × 16 = 720,
21/45 = 21 × 16/45 × 16 = 336/720 - Likewise, for the 2nd fraction, since 16 × 45 = 720,
81/16 = 81 × 45/16 × 45 = 3645/720 - Subtract the two like fractions:
336/720 - 3645/720 = 336 - 3645/720 = -3309/720 - After reducing the fraction, the answer is -1103/240
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