Add 18/8 and 54/21
1st number: 2 2/8, 2nd number: 2 12/21
18/8 + 54/21 is 135/28.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 8 and 21 is 168
Next, find the equivalent fraction of both fractional numbers with denominator 168 - For the 1st fraction, since 8 × 21 = 168,
18/8 = 18 × 21/8 × 21 = 378/168 - Likewise, for the 2nd fraction, since 21 × 8 = 168,
54/21 = 54 × 8/21 × 8 = 432/168 - Add the two like fractions:
378/168 + 432/168 = 378 + 432/168 = 810/168 - 810/168 simplified gives 135/28
- So, 18/8 + 54/21 = 135/28
In mixed form: 423/28
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