Subtract 15/80 from 90/70
1st number: 1 20/70, 2nd number: 15/80
90/70 - 15/80 is 123/112.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 70 and 80 is 560
Next, find the equivalent fraction of both fractional numbers with denominator 560 - For the 1st fraction, since 70 × 8 = 560,
90/70 = 90 × 8/70 × 8 = 720/560 - Likewise, for the 2nd fraction, since 80 × 7 = 560,
15/80 = 15 × 7/80 × 7 = 105/560 - Subtract the two like fractions:
720/560 - 105/560 = 720 - 105/560 = 615/560 - After reducing the fraction, the answer is 123/112
- In mixed form: 111/112
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