Subtract 12/8 from 21/45
1st number: 21/45, 2nd number: 1 4/8
21/45 - 12/8 is -31/30.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 45 and 8 is 360
Next, find the equivalent fraction of both fractional numbers with denominator 360 - For the 1st fraction, since 45 × 8 = 360,
21/45 = 21 × 8/45 × 8 = 168/360 - Likewise, for the 2nd fraction, since 8 × 45 = 360,
12/8 = 12 × 45/8 × 45 = 540/360 - Subtract the two like fractions:
168/360 - 540/360 = 168 - 540/360 = -372/360 - After reducing the fraction, the answer is -31/30
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