Subtract 7/40 from 81/18
1st number: 4 9/18, 2nd number: 7/40
81/18 - 7/40 is 173/40.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 18 and 40 is 360
Next, find the equivalent fraction of both fractional numbers with denominator 360 - For the 1st fraction, since 18 × 20 = 360,
81/18 = 81 × 20/18 × 20 = 1620/360 - Likewise, for the 2nd fraction, since 40 × 9 = 360,
7/40 = 7 × 9/40 × 9 = 63/360 - Subtract the two like fractions:
1620/360 - 63/360 = 1620 - 63/360 = 1557/360 - After reducing the fraction, the answer is 173/40
- In mixed form: 413/40
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