Add 21/3 and 42/84
1st number: 7 0/3, 2nd number: 42/84
21/3 + 42/84 is 15/2.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 3 and 84 is 84
Next, find the equivalent fraction of both fractional numbers with denominator 84 - For the 1st fraction, since 3 × 28 = 84,
21/3 = 21 × 28/3 × 28 = 588/84 - Likewise, for the 2nd fraction, since 84 × 1 = 84,
42/84 = 42 × 1/84 × 1 = 42/84 - Add the two like fractions:
588/84 + 42/84 = 588 + 42/84 = 630/84 - 630/84 simplified gives 15/2
- So, 21/3 + 42/84 = 15/2
In mixed form: 71/2
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