Subtract 90/70 from 30/40
1st number: 30/40, 2nd number: 1 20/70
30/40 - 90/70 is -15/28.
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,
30/40 = 30 × 7/40 × 7 = 210/280 - Likewise, for the 2nd fraction, since 70 × 4 = 280,
90/70 = 90 × 4/70 × 4 = 360/280 - Subtract the two like fractions:
210/280 - 360/280 = 210 - 360/280 = -150/280 - After reducing the fraction, the answer is -15/28
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