Add 21/42 and 7/8
21/42 + 7/8 is 11/8.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 42 and 8 is 168
Next, find the equivalent fraction of both fractional numbers with denominator 168 - For the 1st fraction, since 42 × 4 = 168,
21/42 = 21 × 4/42 × 4 = 84/168 - Likewise, for the 2nd fraction, since 8 × 21 = 168,
7/8 = 7 × 21/8 × 21 = 147/168 - Add the two like fractions:
84/168 + 147/168 = 84 + 147/168 = 231/168 - 231/168 simplified gives 11/8
- So, 21/42 + 7/8 = 11/8
In mixed form: 13/8
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