Subtract 3/80 from 90/70
1st number: 1 20/70, 2nd number: 3/80
90/70 - 3/80 is 699/560.
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,
3/80 = 3 × 7/80 × 7 = 21/560 - Subtract the two like fractions:
720/560 - 21/560 = 720 - 21/560 = 699/560 - In mixed form: 1139/560
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