Add 20/8 and 81/21
1st number: 2 4/8, 2nd number: 3 18/21
20/8 + 81/21 is 89/14.
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,
81/21 = 81 × 8/21 × 8 = 648/168 - Add the two like fractions:
420/168 + 648/168 = 420 + 648/168 = 1068/168 - 1068/168 simplified gives 89/14
- So, 20/8 + 81/21 = 89/14
In mixed form: 65/14
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