Subtract 9/90 from 4/80
4/80 - 9/90 is -1/20.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 80 and 90 is 720
Next, find the equivalent fraction of both fractional numbers with denominator 720 - For the 1st fraction, since 80 × 9 = 720,
4/80 = 4 × 9/80 × 9 = 36/720 - Likewise, for the 2nd fraction, since 90 × 8 = 720,
9/90 = 9 × 8/90 × 8 = 72/720 - Subtract the two like fractions:
36/720 - 72/720 = 36 - 72/720 = -36/720 - After reducing the fraction, the answer is -1/20
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