Add 42/84 and 15/12
1st number: 42/84, 2nd number: 1 3/12
42/84 + 15/12 is 7/4.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 84 and 12 is 84
Next, find the equivalent fraction of both fractional numbers with denominator 84 - For the 1st fraction, since 84 × 1 = 84,
42/84 = 42 × 1/84 × 1 = 42/84 - Likewise, for the 2nd fraction, since 12 × 7 = 84,
15/12 = 15 × 7/12 × 7 = 105/84 - Add the two like fractions:
42/84 + 105/84 = 42 + 105/84 = 147/84 - 147/84 simplified gives 7/4
- So, 42/84 + 15/12 = 7/4
In mixed form: 13/4
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