Subtract 7/10 from 20/90
20/90 - 7/10 is -43/90.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 90 and 10 is 90
Next, find the equivalent fraction of both fractional numbers with denominator 90 - For the 1st fraction, since 90 × 1 = 90,
20/90 = 20 × 1/90 × 1 = 20/90 - Likewise, for the 2nd fraction, since 10 × 9 = 90,
7/10 = 7 × 9/10 × 9 = 63/90 - Subtract the two like fractions:
20/90 - 63/90 = 20 - 63/90 = -43/90
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