Add 15/4 and 21/42
1st number: 3 3/4, 2nd number: 21/42
15/4 + 21/42 is 17/4.
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,
15/4 = 15 × 21/4 × 21 = 315/84 - Likewise, for the 2nd fraction, since 42 × 2 = 84,
21/42 = 21 × 2/42 × 2 = 42/84 - Add the two like fractions:
315/84 + 42/84 = 315 + 42/84 = 357/84 - 357/84 simplified gives 17/4
- So, 15/4 + 21/42 = 17/4
In mixed form: 41/4
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