Add 7/84 and 42/21
1st number: 7/84, 2nd number: 2 0/21
7/84 + 42/21 is 25/12.
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,
7/84 = 7 × 1/84 × 1 = 7/84 - Likewise, for the 2nd fraction, since 21 × 4 = 84,
42/21 = 42 × 4/21 × 4 = 168/84 - Add the two like fractions:
7/84 + 168/84 = 7 + 168/84 = 175/84 - 175/84 simplified gives 25/12
- So, 7/84 + 42/21 = 25/12
In mixed form: 21/12
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