Add 21/4 and 15/42
1st number: 5 1/4, 2nd number: 15/42
21/4 + 15/42 is 157/28.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 4 and 42 is 84
Next, find the equivalent fraction of both fractional numbers with denominator 84 - For the 1st fraction, since 4 × 21 = 84,
21/4 = 21 × 21/4 × 21 = 441/84 - Likewise, for the 2nd fraction, since 42 × 2 = 84,
15/42 = 15 × 2/42 × 2 = 30/84 - Add the two like fractions:
441/84 + 30/84 = 441 + 30/84 = 471/84 - 471/84 simplified gives 157/28
- So, 21/4 + 15/42 = 157/28
In mixed form: 517/28
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