Subtract 9/20 from 7/90
7/90 - 9/20 is -67/180.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 90 and 20 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 20 × 9 = 180,
9/20 = 9 × 9/20 × 9 = 81/180 - Subtract the two like fractions:
14/180 - 81/180 = 14 - 81/180 = -67/180
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