Add 21/6 and 81/40
1st number: 3 3/6, 2nd number: 2 1/40
21/6 + 81/40 is 221/40.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 6 and 40 is 120
Next, find the equivalent fraction of both fractional numbers with denominator 120 - For the 1st fraction, since 6 × 20 = 120,
21/6 = 21 × 20/6 × 20 = 420/120 - Likewise, for the 2nd fraction, since 40 × 3 = 120,
81/40 = 81 × 3/40 × 3 = 243/120 - Add the two like fractions:
420/120 + 243/120 = 420 + 243/120 = 663/120 - 663/120 simplified gives 221/40
- So, 21/6 + 81/40 = 221/40
In mixed form: 521/40
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