Add 21/5 and 21/20
1st number: 4 1/5, 2nd number: 1 1/20
21/5 + 21/20 is 21/4.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 5 and 20 is 20
Next, find the equivalent fraction of both fractional numbers with denominator 20 - For the 1st fraction, since 5 × 4 = 20,
21/5 = 21 × 4/5 × 4 = 84/20 - Likewise, for the 2nd fraction, since 20 × 1 = 20,
21/20 = 21 × 1/20 × 1 = 21/20 - Add the two like fractions:
84/20 + 21/20 = 84 + 21/20 = 105/20 - 105/20 simplified gives 21/4
- So, 21/5 + 21/20 = 21/4
In mixed form: 51/4
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