Add 5/8 and 21/15
1st number: 5/8, 2nd number: 1 6/15
5/8 + 21/15 is 81/40.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 8 and 15 is 120
Next, find the equivalent fraction of both fractional numbers with denominator 120 - For the 1st fraction, since 8 × 15 = 120,
5/8 = 5 × 15/8 × 15 = 75/120 - Likewise, for the 2nd fraction, since 15 × 8 = 120,
21/15 = 21 × 8/15 × 8 = 168/120 - Add the two like fractions:
75/120 + 168/120 = 75 + 168/120 = 243/120 - 243/120 simplified gives 81/40
- So, 5/8 + 21/15 = 81/40
In mixed form: 21/40
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