Add 21/3 and 90/7
1st number: 7 0/3, 2nd number: 12 6/7
21/3 + 90/7 is 139/7.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 3 and 7 is 21
Next, find the equivalent fraction of both fractional numbers with denominator 21 - For the 1st fraction, since 3 × 7 = 21,
21/3 = 21 × 7/3 × 7 = 147/21 - Likewise, for the 2nd fraction, since 7 × 3 = 21,
90/7 = 90 × 3/7 × 3 = 270/21 - Add the two like fractions:
147/21 + 270/21 = 147 + 270/21 = 417/21 - 417/21 simplified gives 139/7
- So, 21/3 + 90/7 = 139/7
In mixed form: 196/7
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