Add 21/42 and 5/4
1st number: 21/42, 2nd number: 1 1/4
21/42 + 5/4 is 7/4.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 42 and 4 is 84
Next, find the equivalent fraction of both fractional numbers with denominator 84 - For the 1st fraction, since 42 × 2 = 84,
21/42 = 21 × 2/42 × 2 = 42/84 - Likewise, for the 2nd fraction, since 4 × 21 = 84,
5/4 = 5 × 21/4 × 21 = 105/84 - Add the two like fractions:
42/84 + 105/84 = 42 + 105/84 = 147/84 - 147/84 simplified gives 7/4
- So, 21/42 + 5/4 = 7/4
In mixed form: 13/4
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