Add 21/12 and 84/42
1st number: 1 9/12, 2nd number: 2 0/42
21/12 + 84/42 is 15/4.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 12 and 42 is 84
Next, find the equivalent fraction of both fractional numbers with denominator 84 - For the 1st fraction, since 12 × 7 = 84,
21/12 = 21 × 7/12 × 7 = 147/84 - Likewise, for the 2nd fraction, since 42 × 2 = 84,
84/42 = 84 × 2/42 × 2 = 168/84 - Add the two like fractions:
147/84 + 168/84 = 147 + 168/84 = 315/84 - 315/84 simplified gives 15/4
- So, 21/12 + 84/42 = 15/4
In mixed form: 33/4
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