Add 90/8 and 30/21
1st number: 11 2/8, 2nd number: 1 9/21
90/8 + 30/21 is 355/28.
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,
90/8 = 90 × 21/8 × 21 = 1890/168 - Likewise, for the 2nd fraction, since 21 × 8 = 168,
30/21 = 30 × 8/21 × 8 = 240/168 - Add the two like fractions:
1890/168 + 240/168 = 1890 + 240/168 = 2130/168 - 2130/168 simplified gives 355/28
- So, 90/8 + 30/21 = 355/28
In mixed form: 1219/28
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