Subtract 28/80 from 21/45
21/45 - 28/80 is 7/60.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 45 and 80 is 720
Next, find the equivalent fraction of both fractional numbers with denominator 720 - For the 1st fraction, since 45 × 16 = 720,
21/45 = 21 × 16/45 × 16 = 336/720 - Likewise, for the 2nd fraction, since 80 × 9 = 720,
28/80 = 28 × 9/80 × 9 = 252/720 - Subtract the two like fractions:
336/720 - 252/720 = 336 - 252/720 = 84/720 - After reducing the fraction, the answer is 7/60
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