Subtract 4/80 from 21/90
21/90 - 4/80 is 11/60.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 90 and 80 is 720
Next, find the equivalent fraction of both fractional numbers with denominator 720 - For the 1st fraction, since 90 × 8 = 720,
21/90 = 21 × 8/90 × 8 = 168/720 - Likewise, for the 2nd fraction, since 80 × 9 = 720,
4/80 = 4 × 9/80 × 9 = 36/720 - Subtract the two like fractions:
168/720 - 36/720 = 168 - 36/720 = 132/720 - After reducing the fraction, the answer is 11/60
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