Subtract 21/7 from 15/80
1st number: 15/80, 2nd number: 3 0/7
15/80 - 21/7 is -45/16.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 80 and 7 is 560
Next, find the equivalent fraction of both fractional numbers with denominator 560 - For the 1st fraction, since 80 × 7 = 560,
15/80 = 15 × 7/80 × 7 = 105/560 - Likewise, for the 2nd fraction, since 7 × 80 = 560,
21/7 = 21 × 80/7 × 80 = 1680/560 - Subtract the two like fractions:
105/560 - 1680/560 = 105 - 1680/560 = -1575/560 - After reducing the fraction, the answer is -45/16
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