Add 21/8 and 81/30
1st number: 2 5/8, 2nd number: 2 21/30
21/8 + 81/30 is 213/40.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 8 and 30 is 120
Next, find the equivalent fraction of both fractional numbers with denominator 120 - For the 1st fraction, since 8 × 15 = 120,
21/8 = 21 × 15/8 × 15 = 315/120 - Likewise, for the 2nd fraction, since 30 × 4 = 120,
81/30 = 81 × 4/30 × 4 = 324/120 - Add the two like fractions:
315/120 + 324/120 = 315 + 324/120 = 639/120 - 639/120 simplified gives 213/40
- So, 21/8 + 81/30 = 213/40
In mixed form: 513/40
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