Add 18/2 and 72/21
1st number: 9 0/2, 2nd number: 3 9/21
18/2 + 72/21 is 87/7.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 2 and 21 is 42
Next, find the equivalent fraction of both fractional numbers with denominator 42 - For the 1st fraction, since 2 × 21 = 42,
18/2 = 18 × 21/2 × 21 = 378/42 - Likewise, for the 2nd fraction, since 21 × 2 = 42,
72/21 = 72 × 2/21 × 2 = 144/42 - Add the two like fractions:
378/42 + 144/42 = 378 + 144/42 = 522/42 - 522/42 simplified gives 87/7
- So, 18/2 + 72/21 = 87/7
In mixed form: 123/7
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