Add 18/21 and 15/63
18/21 + 15/63 is 23/21.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 63 is 63
Next, find the equivalent fraction of both fractional numbers with denominator 63 - For the 1st fraction, since 21 × 3 = 63,
18/21 = 18 × 3/21 × 3 = 54/63 - Likewise, for the 2nd fraction, since 63 × 1 = 63,
15/63 = 15 × 1/63 × 1 = 15/63 - Add the two like fractions:
54/63 + 15/63 = 54 + 15/63 = 69/63 - 69/63 simplified gives 23/21
- So, 18/21 + 15/63 = 23/21
In mixed form: 12/21
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