Add 21/4 and 81/7
1st number: 5 1/4, 2nd number: 11 4/7
21/4 + 81/7 is 471/28.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 4 and 7 is 28
Next, find the equivalent fraction of both fractional numbers with denominator 28 - For the 1st fraction, since 4 × 7 = 28,
21/4 = 21 × 7/4 × 7 = 147/28 - Likewise, for the 2nd fraction, since 7 × 4 = 28,
81/7 = 81 × 4/7 × 4 = 324/28 - Add the two like fractions:
147/28 + 324/28 = 147 + 324/28 = 471/28 - So, 21/4 + 81/7 = 471/28
In mixed form: 1623/28
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