Add 20/5 and 21/84
1st number: 4 0/5, 2nd number: 21/84
20/5 + 21/84 is 17/4.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 5 and 84 is 420
Next, find the equivalent fraction of both fractional numbers with denominator 420 - For the 1st fraction, since 5 × 84 = 420,
20/5 = 20 × 84/5 × 84 = 1680/420 - Likewise, for the 2nd fraction, since 84 × 5 = 420,
21/84 = 21 × 5/84 × 5 = 105/420 - Add the two like fractions:
1680/420 + 105/420 = 1680 + 105/420 = 1785/420 - 1785/420 simplified gives 17/4
- So, 20/5 + 21/84 = 17/4
In mixed form: 41/4
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