Add 20/21 and 54/8
1st number: 20/21, 2nd number: 6 6/8
20/21 + 54/8 is 647/84.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 8 is 168
Next, find the equivalent fraction of both fractional numbers with denominator 168 - For the 1st fraction, since 21 × 8 = 168,
20/21 = 20 × 8/21 × 8 = 160/168 - Likewise, for the 2nd fraction, since 8 × 21 = 168,
54/8 = 54 × 21/8 × 21 = 1134/168 - Add the two like fractions:
160/168 + 1134/168 = 160 + 1134/168 = 1294/168 - 1294/168 simplified gives 647/84
- So, 20/21 + 54/8 = 647/84
In mixed form: 759/84
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