Subtract 90/70 from 72/40
1st number: 1 32/40, 2nd number: 1 20/70
72/40 - 90/70 is 18/35.
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,
72/40 = 72 × 7/40 × 7 = 504/280 - Likewise, for the 2nd fraction, since 70 × 4 = 280,
90/70 = 90 × 4/70 × 4 = 360/280 - Subtract the two like fractions:
504/280 - 360/280 = 504 - 360/280 = 144/280 - After reducing the fraction, the answer is 18/35
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