Add 42/84 and 84/21
1st number: 42/84, 2nd number: 4 0/21
42/84 + 84/21 is 9/2.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 84 and 21 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 21 × 4 = 84,
84/21 = 84 × 4/21 × 4 = 336/84 - Add the two like fractions:
42/84 + 336/84 = 42 + 336/84 = 378/84 - 378/84 simplified gives 9/2
- So, 42/84 + 84/21 = 9/2
In mixed form: 41/2
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