Subtract 3/45 from 21/80
21/80 - 3/45 is 47/240.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 80 and 45 is 720
Next, find the equivalent fraction of both fractional numbers with denominator 720 - For the 1st fraction, since 80 × 9 = 720,
21/80 = 21 × 9/80 × 9 = 189/720 - Likewise, for the 2nd fraction, since 45 × 16 = 720,
3/45 = 3 × 16/45 × 16 = 48/720 - Subtract the two like fractions:
189/720 - 48/720 = 189 - 48/720 = 141/720 - After reducing the fraction, the answer is 47/240
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