Subtract 21/80 from 9/10
9/10 - 21/80 is 51/80.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 10 and 80 is 80
Next, find the equivalent fraction of both fractional numbers with denominator 80 - For the 1st fraction, since 10 × 8 = 80,
9/10 = 9 × 8/10 × 8 = 72/80 - Likewise, for the 2nd fraction, since 80 × 1 = 80,
21/80 = 21 × 1/80 × 1 = 21/80 - Subtract the two like fractions:
72/80 - 21/80 = 72 - 21/80 = 51/80
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