Add 21/7 and 5/81
1st number: 3 0/7, 2nd number: 5/81
21/7 + 5/81 is 248/81.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 7 and 81 is 567
Next, find the equivalent fraction of both fractional numbers with denominator 567 - For the 1st fraction, since 7 × 81 = 567,
21/7 = 21 × 81/7 × 81 = 1701/567 - Likewise, for the 2nd fraction, since 81 × 7 = 567,
5/81 = 5 × 7/81 × 7 = 35/567 - Add the two like fractions:
1701/567 + 35/567 = 1701 + 35/567 = 1736/567 - 1736/567 simplified gives 248/81
- So, 21/7 + 5/81 = 248/81
In mixed form: 35/81
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