Add 84/4 and 72/21
1st number: 21 0/4, 2nd number: 3 9/21
84/4 + 72/21 is 171/7.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 4 and 21 is 84
Next, find the equivalent fraction of both fractional numbers with denominator 84 - For the 1st fraction, since 4 × 21 = 84,
84/4 = 84 × 21/4 × 21 = 1764/84 - Likewise, for the 2nd fraction, since 21 × 4 = 84,
72/21 = 72 × 4/21 × 4 = 288/84 - Add the two like fractions:
1764/84 + 288/84 = 1764 + 288/84 = 2052/84 - 2052/84 simplified gives 171/7
- So, 84/4 + 72/21 = 171/7
In mixed form: 243/7
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