Add 7/21 and 90/8
1st number: 7/21, 2nd number: 11 2/8
7/21 + 90/8 is 139/12.
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,
7/21 = 7 × 8/21 × 8 = 56/168 - Likewise, for the 2nd fraction, since 8 × 21 = 168,
90/8 = 90 × 21/8 × 21 = 1890/168 - Add the two like fractions:
56/168 + 1890/168 = 56 + 1890/168 = 1946/168 - 1946/168 simplified gives 139/12
- So, 7/21 + 90/8 = 139/12
In mixed form: 117/12
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