Add 30/21 and 30/42
1st number: 1 9/21, 2nd number: 30/42
30/21 + 30/42 is 15/7.
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,
30/21 = 30 × 2/21 × 2 = 60/42 - Likewise, for the 2nd fraction, since 42 × 1 = 42,
30/42 = 30 × 1/42 × 1 = 30/42 - Add the two like fractions:
60/42 + 30/42 = 60 + 30/42 = 90/42 - 90/42 simplified gives 15/7
- So, 30/21 + 30/42 = 15/7
In mixed form: 21/7
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