Add 20/8 and 54/21
1st number: 2 4/8, 2nd number: 2 12/21
20/8 + 54/21 is 71/14.
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,
20/8 = 20 × 21/8 × 21 = 420/168 - Likewise, for the 2nd fraction, since 21 × 8 = 168,
54/21 = 54 × 8/21 × 8 = 432/168 - Add the two like fractions:
420/168 + 432/168 = 420 + 432/168 = 852/168 - 852/168 simplified gives 71/14
- So, 20/8 + 54/21 = 71/14
In mixed form: 51/14
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