Add 81/18 and 30/40
1st number: 4 9/18, 2nd number: 30/40
81/18 + 30/40 is 21/4.
Steps for adding 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,
30/40 = 30 × 9/40 × 9 = 270/360 - Add the two like fractions:
1620/360 + 270/360 = 1620 + 270/360 = 1890/360 - 1890/360 simplified gives 21/4
- So, 81/18 + 30/40 = 21/4
In mixed form: 51/4
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