Add 30/8 and 21/18
1st number: 3 6/8, 2nd number: 1 3/18
30/8 + 21/18 is 59/12.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 8 and 18 is 72
Next, find the equivalent fraction of both fractional numbers with denominator 72 - For the 1st fraction, since 8 × 9 = 72,
30/8 = 30 × 9/8 × 9 = 270/72 - Likewise, for the 2nd fraction, since 18 × 4 = 72,
21/18 = 21 × 4/18 × 4 = 84/72 - Add the two like fractions:
270/72 + 84/72 = 270 + 84/72 = 354/72 - 354/72 simplified gives 59/12
- So, 30/8 + 21/18 = 59/12
In mixed form: 411/12
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