Add 18/84 and 21/5
1st number: 18/84, 2nd number: 4 1/5
18/84 + 21/5 is 309/70.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 84 and 5 is 420
Next, find the equivalent fraction of both fractional numbers with denominator 420 - For the 1st fraction, since 84 × 5 = 420,
18/84 = 18 × 5/84 × 5 = 90/420 - Likewise, for the 2nd fraction, since 5 × 84 = 420,
21/5 = 21 × 84/5 × 84 = 1764/420 - Add the two like fractions:
90/420 + 1764/420 = 90 + 1764/420 = 1854/420 - 1854/420 simplified gives 309/70
- So, 18/84 + 21/5 = 309/70
In mixed form: 429/70
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