Add 18/15 and 21/42
1st number: 1 3/15, 2nd number: 21/42
18/15 + 21/42 is 17/10.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 15 and 42 is 210
Next, find the equivalent fraction of both fractional numbers with denominator 210 - For the 1st fraction, since 15 × 14 = 210,
18/15 = 18 × 14/15 × 14 = 252/210 - Likewise, for the 2nd fraction, since 42 × 5 = 210,
21/42 = 21 × 5/42 × 5 = 105/210 - Add the two like fractions:
252/210 + 105/210 = 252 + 105/210 = 357/210 - 357/210 simplified gives 17/10
- So, 18/15 + 21/42 = 17/10
In mixed form: 17/10
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