Add 21/12 and 54/72
1st number: 1 9/12, 2nd number: 54/72
21/12 + 54/72 is 5/2.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 12 and 72 is 72
Next, find the equivalent fraction of both fractional numbers with denominator 72 - For the 1st fraction, since 12 × 6 = 72,
21/12 = 21 × 6/12 × 6 = 126/72 - Likewise, for the 2nd fraction, since 72 × 1 = 72,
54/72 = 54 × 1/72 × 1 = 54/72 - Add the two like fractions:
126/72 + 54/72 = 126 + 54/72 = 180/72 - 180/72 simplified gives 5/2
- So, 21/12 + 54/72 = 5/2
In mixed form: 21/2
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