Subtract 7/12 from 21/90
21/90 - 7/12 is -7/20.
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,
21/90 = 21 × 2/90 × 2 = 42/180 - Likewise, for the 2nd fraction, since 12 × 15 = 180,
7/12 = 7 × 15/12 × 15 = 105/180 - Subtract the two like fractions:
42/180 - 105/180 = 42 - 105/180 = -63/180 - After reducing the fraction, the answer is -7/20
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