Subtract 4/20 from 4/90
4/90 - 4/20 is -7/45.
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,
4/90 = 4 × 2/90 × 2 = 8/180 - Likewise, for the 2nd fraction, since 20 × 9 = 180,
4/20 = 4 × 9/20 × 9 = 36/180 - Subtract the two like fractions:
8/180 - 36/180 = 8 - 36/180 = -28/180 - After reducing the fraction, the answer is -7/45
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