Add 81/15 and 21/7
1st number: 5 6/15, 2nd number: 3 0/7
81/15 + 21/7 is 42/5.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 15 and 7 is 105
Next, find the equivalent fraction of both fractional numbers with denominator 105 - For the 1st fraction, since 15 × 7 = 105,
81/15 = 81 × 7/15 × 7 = 567/105 - Likewise, for the 2nd fraction, since 7 × 15 = 105,
21/7 = 21 × 15/7 × 15 = 315/105 - Add the two like fractions:
567/105 + 315/105 = 567 + 315/105 = 882/105 - 882/105 simplified gives 42/5
- So, 81/15 + 21/7 = 42/5
In mixed form: 82/5
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