Add 72/9 and 21/42
1st number: 8 0/9, 2nd number: 21/42
72/9 + 21/42 is 17/2.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 9 and 42 is 126
Next, find the equivalent fraction of both fractional numbers with denominator 126 - For the 1st fraction, since 9 × 14 = 126,
72/9 = 72 × 14/9 × 14 = 1008/126 - Likewise, for the 2nd fraction, since 42 × 3 = 126,
21/42 = 21 × 3/42 × 3 = 63/126 - Add the two like fractions:
1008/126 + 63/126 = 1008 + 63/126 = 1071/126 - 1071/126 simplified gives 17/2
- So, 72/9 + 21/42 = 17/2
In mixed form: 81/2
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