Add 21/5 and 81/7
1st number: 4 1/5, 2nd number: 11 4/7
21/5 + 81/7 is 552/35.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 5 and 7 is 35
Next, find the equivalent fraction of both fractional numbers with denominator 35 - For the 1st fraction, since 5 × 7 = 35,
21/5 = 21 × 7/5 × 7 = 147/35 - Likewise, for the 2nd fraction, since 7 × 5 = 35,
81/7 = 81 × 5/7 × 5 = 405/35 - Add the two like fractions:
147/35 + 405/35 = 147 + 405/35 = 552/35 - So, 21/5 + 81/7 = 552/35
In mixed form: 1527/35
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