Add 81/30 and 15/40
1st number: 2 21/30, 2nd number: 15/40
81/30 + 15/40 is 123/40.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 30 and 40 is 120
Next, find the equivalent fraction of both fractional numbers with denominator 120 - For the 1st fraction, since 30 × 4 = 120,
81/30 = 81 × 4/30 × 4 = 324/120 - Likewise, for the 2nd fraction, since 40 × 3 = 120,
15/40 = 15 × 3/40 × 3 = 45/120 - Add the two like fractions:
324/120 + 45/120 = 324 + 45/120 = 369/120 - 369/120 simplified gives 123/40
- So, 81/30 + 15/40 = 123/40
In mixed form: 33/40
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