Subtract 72/18 from 70/40
1st number: 1 30/40, 2nd number: 4 0/18
70/40 - 72/18 is -9/4.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 40 and 18 is 360
Next, find the equivalent fraction of both fractional numbers with denominator 360 - For the 1st fraction, since 40 × 9 = 360,
70/40 = 70 × 9/40 × 9 = 630/360 - Likewise, for the 2nd fraction, since 18 × 20 = 360,
72/18 = 72 × 20/18 × 20 = 1440/360 - Subtract the two like fractions:
630/360 - 1440/360 = 630 - 1440/360 = -810/360 - After reducing the fraction, the answer is -9/4
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