Add 15/18 and 30/40
15/18 + 30/40 is 19/12.
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,
15/18 = 15 × 20/18 × 20 = 300/360 - Likewise, for the 2nd fraction, since 40 × 9 = 360,
30/40 = 30 × 9/40 × 9 = 270/360 - Add the two like fractions:
300/360 + 270/360 = 300 + 270/360 = 570/360 - 570/360 simplified gives 19/12
- So, 15/18 + 30/40 = 19/12
In mixed form: 17/12
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