Subtract 12/8 from 21/90
1st number: 21/90, 2nd number: 1 4/8
21/90 - 12/8 is -19/15.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 90 and 8 is 360
Next, find the equivalent fraction of both fractional numbers with denominator 360 - For the 1st fraction, since 90 × 4 = 360,
21/90 = 21 × 4/90 × 4 = 84/360 - Likewise, for the 2nd fraction, since 8 × 45 = 360,
12/8 = 12 × 45/8 × 45 = 540/360 - Subtract the two like fractions:
84/360 - 540/360 = 84 - 540/360 = -456/360 - After reducing the fraction, the answer is -19/15
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