Add 21/4 and 15/28
1st number: 5 1/4, 2nd number: 15/28
21/4 + 15/28 is 81/14.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 4 and 28 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 28 × 1 = 28,
15/28 = 15 × 1/28 × 1 = 15/28 - Add the two like fractions:
147/28 + 15/28 = 147 + 15/28 = 162/28 - 162/28 simplified gives 81/14
- So, 21/4 + 15/28 = 81/14
In mixed form: 511/14
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