Subtract 21/60 from 7/90
7/90 - 21/60 is -49/180.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 90 and 60 is 180
Next, find the equivalent fraction of both fractional numbers with denominator 180 - For the 1st fraction, since 90 × 2 = 180,
7/90 = 7 × 2/90 × 2 = 14/180 - Likewise, for the 2nd fraction, since 60 × 3 = 180,
21/60 = 21 × 3/60 × 3 = 63/180 - Subtract the two like fractions:
14/180 - 63/180 = 14 - 63/180 = -49/180
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