Subtract 72/21 from 80/45
1st number: 1 35/45, 2nd number: 3 9/21
80/45 - 72/21 is -104/63.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 45 and 21 is 315
Next, find the equivalent fraction of both fractional numbers with denominator 315 - For the 1st fraction, since 45 × 7 = 315,
80/45 = 80 × 7/45 × 7 = 560/315 - Likewise, for the 2nd fraction, since 21 × 15 = 315,
72/21 = 72 × 15/21 × 15 = 1080/315 - Subtract the two like fractions:
560/315 - 1080/315 = 560 - 1080/315 = -520/315 - After reducing the fraction, the answer is -104/63
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