Add 21/8 and 72/5
1st number: 2 5/8, 2nd number: 14 2/5
21/8 + 72/5 is 681/40.
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,
72/5 = 72 × 8/5 × 8 = 576/40 - Add the two like fractions:
105/40 + 576/40 = 105 + 576/40 = 681/40 - So, 21/8 + 72/5 = 681/40
In mixed form: 171/40
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