Add 27/21 and 18/42
1st number: 1 6/21, 2nd number: 18/42
27/21 + 18/42 is 12/7.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 42 is 42
Next, find the equivalent fraction of both fractional numbers with denominator 42 - For the 1st fraction, since 21 × 2 = 42,
27/21 = 27 × 2/21 × 2 = 54/42 - Likewise, for the 2nd fraction, since 42 × 1 = 42,
18/42 = 18 × 1/42 × 1 = 18/42 - Add the two like fractions:
54/42 + 18/42 = 54 + 18/42 = 72/42 - 72/42 simplified gives 12/7
- So, 27/21 + 18/42 = 12/7
In mixed form: 15/7
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