Subtract 45/21 from 15/8
1st number: 1 7/8, 2nd number: 2 3/21
15/8 - 45/21 is -15/56.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 8 and 21 is 168
Next, find the equivalent fraction of both fractional numbers with denominator 168 - For the 1st fraction, since 8 × 21 = 168,
15/8 = 15 × 21/8 × 21 = 315/168 - Likewise, for the 2nd fraction, since 21 × 8 = 168,
45/21 = 45 × 8/21 × 8 = 360/168 - Subtract the two like fractions:
315/168 - 360/168 = 315 - 360/168 = -45/168 - After reducing the fraction, the answer is -15/56
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