Subtract 21/8 from 45/21
1st number: 2 3/21, 2nd number: 2 5/8
45/21 - 21/8 is -27/56.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 8 is 168
Next, find the equivalent fraction of both fractional numbers with denominator 168 - For the 1st fraction, since 21 × 8 = 168,
45/21 = 45 × 8/21 × 8 = 360/168 - Likewise, for the 2nd fraction, since 8 × 21 = 168,
21/8 = 21 × 21/8 × 21 = 441/168 - Subtract the two like fractions:
360/168 - 441/168 = 360 - 441/168 = -81/168 - After reducing the fraction, the answer is -27/56
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