Add 15/30 and 81/42
1st number: 15/30, 2nd number: 1 39/42
15/30 + 81/42 is 17/7.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 30 and 42 is 210
Next, find the equivalent fraction of both fractional numbers with denominator 210 - For the 1st fraction, since 30 × 7 = 210,
15/30 = 15 × 7/30 × 7 = 105/210 - Likewise, for the 2nd fraction, since 42 × 5 = 210,
81/42 = 81 × 5/42 × 5 = 405/210 - Add the two like fractions:
105/210 + 405/210 = 105 + 405/210 = 510/210 - 510/210 simplified gives 17/7
- So, 15/30 + 81/42 = 17/7
In mixed form: 23/7
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