Add 30/36 and 54/21
1st number: 30/36, 2nd number: 2 12/21
30/36 + 54/21 is 143/42.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 36 and 21 is 252
Next, find the equivalent fraction of both fractional numbers with denominator 252 - For the 1st fraction, since 36 × 7 = 252,
30/36 = 30 × 7/36 × 7 = 210/252 - Likewise, for the 2nd fraction, since 21 × 12 = 252,
54/21 = 54 × 12/21 × 12 = 648/252 - Add the two like fractions:
210/252 + 648/252 = 210 + 648/252 = 858/252 - 858/252 simplified gives 143/42
- So, 30/36 + 54/21 = 143/42
In mixed form: 317/42
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