Add 21/30 and 15/8
1st number: 21/30, 2nd number: 1 7/8
21/30 + 15/8 is 103/40.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 30 and 8 is 120
Next, find the equivalent fraction of both fractional numbers with denominator 120 - For the 1st fraction, since 30 × 4 = 120,
21/30 = 21 × 4/30 × 4 = 84/120 - Likewise, for the 2nd fraction, since 8 × 15 = 120,
15/8 = 15 × 15/8 × 15 = 225/120 - Add the two like fractions:
84/120 + 225/120 = 84 + 225/120 = 309/120 - 309/120 simplified gives 103/40
- So, 21/30 + 15/8 = 103/40
In mixed form: 223/40
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