Add 18/15 and 21/7
1st number: 1 3/15, 2nd number: 3 0/7
18/15 + 21/7 is 21/5.
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,
18/15 = 18 × 7/15 × 7 = 126/105 - Likewise, for the 2nd fraction, since 7 × 15 = 105,
21/7 = 21 × 15/7 × 15 = 315/105 - Add the two like fractions:
126/105 + 315/105 = 126 + 315/105 = 441/105 - 441/105 simplified gives 21/5
- So, 18/15 + 21/7 = 21/5
In mixed form: 41/5
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