Add 90/21 and 12/8
1st number: 4 6/21, 2nd number: 1 4/8
90/21 + 12/8 is 81/14.
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,
90/21 = 90 × 8/21 × 8 = 720/168 - Likewise, for the 2nd fraction, since 8 × 21 = 168,
12/8 = 12 × 21/8 × 21 = 252/168 - Add the two like fractions:
720/168 + 252/168 = 720 + 252/168 = 972/168 - 972/168 simplified gives 81/14
- So, 90/21 + 12/8 = 81/14
In mixed form: 511/14
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