Subtract 21/80 from 3/90
3/90 - 21/80 is -11/48.
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,
3/90 = 3 × 8/90 × 8 = 24/720 - Likewise, for the 2nd fraction, since 80 × 9 = 720,
21/80 = 21 × 9/80 × 9 = 189/720 - Subtract the two like fractions:
24/720 - 189/720 = 24 - 189/720 = -165/720 - After reducing the fraction, the answer is -11/48
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