Subtract 28/90 from 3/12
3/12 - 28/90 is -11/180.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 12 and 90 is 180
Next, find the equivalent fraction of both fractional numbers with denominator 180 - For the 1st fraction, since 12 × 15 = 180,
3/12 = 3 × 15/12 × 15 = 45/180 - Likewise, for the 2nd fraction, since 90 × 2 = 180,
28/90 = 28 × 2/90 × 2 = 56/180 - Subtract the two like fractions:
45/180 - 56/180 = 45 - 56/180 = -11/180
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