Add 21/42 and 54/63
21/42 + 54/63 is 19/14.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 42 and 63 is 126
Next, find the equivalent fraction of both fractional numbers with denominator 126 - For the 1st fraction, since 42 × 3 = 126,
21/42 = 21 × 3/42 × 3 = 63/126 - Likewise, for the 2nd fraction, since 63 × 2 = 126,
54/63 = 54 × 2/63 × 2 = 108/126 - Add the two like fractions:
63/126 + 108/126 = 63 + 108/126 = 171/126 - 171/126 simplified gives 19/14
- So, 21/42 + 54/63 = 19/14
In mixed form: 15/14
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