Add 3/12 and 42/21
1st number: 3/12, 2nd number: 2 0/21
3/12 + 42/21 is 9/4.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 12 and 21 is 84
Next, find the equivalent fraction of both fractional numbers with denominator 84 - For the 1st fraction, since 12 × 7 = 84,
3/12 = 3 × 7/12 × 7 = 21/84 - Likewise, for the 2nd fraction, since 21 × 4 = 84,
42/21 = 42 × 4/21 × 4 = 168/84 - Add the two like fractions:
21/84 + 168/84 = 21 + 168/84 = 189/84 - 189/84 simplified gives 9/4
- So, 3/12 + 42/21 = 9/4
In mixed form: 21/4
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