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