Subtract 21/12 from 70/90
1st number: 70/90, 2nd number: 1 9/12
70/90 - 21/12 is -35/36.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 90 and 12 is 180
Next, find the equivalent fraction of both fractional numbers with denominator 180 - For the 1st fraction, since 90 × 2 = 180,
70/90 = 70 × 2/90 × 2 = 140/180 - Likewise, for the 2nd fraction, since 12 × 15 = 180,
21/12 = 21 × 15/12 × 15 = 315/180 - Subtract the two like fractions:
140/180 - 315/180 = 140 - 315/180 = -175/180 - After reducing the fraction, the answer is -35/36
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