Add 21/8 and 21/5
1st number: 2 5/8, 2nd number: 4 1/5
21/8 + 21/5 is 273/40.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 8 and 5 is 40
Next, find the equivalent fraction of both fractional numbers with denominator 40 - For the 1st fraction, since 8 × 5 = 40,
21/8 = 21 × 5/8 × 5 = 105/40 - Likewise, for the 2nd fraction, since 5 × 8 = 40,
21/5 = 21 × 8/5 × 8 = 168/40 - Add the two like fractions:
105/40 + 168/40 = 105 + 168/40 = 273/40 - So, 21/8 + 21/5 = 273/40
In mixed form: 633/40
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