Subtract 80/70 from 70/40
1st number: 1 30/40, 2nd number: 1 10/70
70/40 - 80/70 is 17/28.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 40 and 70 is 280
Next, find the equivalent fraction of both fractional numbers with denominator 280 - For the 1st fraction, since 40 × 7 = 280,
70/40 = 70 × 7/40 × 7 = 490/280 - Likewise, for the 2nd fraction, since 70 × 4 = 280,
80/70 = 80 × 4/70 × 4 = 320/280 - Subtract the two like fractions:
490/280 - 320/280 = 490 - 320/280 = 170/280 - After reducing the fraction, the answer is 17/28
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