Add 21/84 and 42/7
1st number: 21/84, 2nd number: 6 0/7
21/84 + 42/7 is 25/4.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 84 and 7 is 84
Next, find the equivalent fraction of both fractional numbers with denominator 84 - For the 1st fraction, since 84 × 1 = 84,
21/84 = 21 × 1/84 × 1 = 21/84 - Likewise, for the 2nd fraction, since 7 × 12 = 84,
42/7 = 42 × 12/7 × 12 = 504/84 - Add the two like fractions:
21/84 + 504/84 = 21 + 504/84 = 525/84 - 525/84 simplified gives 25/4
- So, 21/84 + 42/7 = 25/4
In mixed form: 61/4
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