Add 81/5 and 21/8
1st number: 16 1/5, 2nd number: 2 5/8
81/5 + 21/8 is 753/40.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 5 and 8 is 40
Next, find the equivalent fraction of both fractional numbers with denominator 40 - For the 1st fraction, since 5 × 8 = 40,
81/5 = 81 × 8/5 × 8 = 648/40 - Likewise, for the 2nd fraction, since 8 × 5 = 40,
21/8 = 21 × 5/8 × 5 = 105/40 - Add the two like fractions:
648/40 + 105/40 = 648 + 105/40 = 753/40 - So, 81/5 + 21/8 = 753/40
In mixed form: 1833/40
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