Add 18/84 and 72/21
1st number: 18/84, 2nd number: 3 9/21
18/84 + 72/21 is 51/14.
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,
18/84 = 18 × 1/84 × 1 = 18/84 - Likewise, for the 2nd fraction, since 21 × 4 = 84,
72/21 = 72 × 4/21 × 4 = 288/84 - Add the two like fractions:
18/84 + 288/84 = 18 + 288/84 = 306/84 - 306/84 simplified gives 51/14
- So, 18/84 + 72/21 = 51/14
In mixed form: 39/14
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