Add 21/54 and 7/8
21/54 + 7/8 is 91/72.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 54 and 8 is 216
Next, find the equivalent fraction of both fractional numbers with denominator 216 - For the 1st fraction, since 54 × 4 = 216,
21/54 = 21 × 4/54 × 4 = 84/216 - Likewise, for the 2nd fraction, since 8 × 27 = 216,
7/8 = 7 × 27/8 × 27 = 189/216 - Add the two like fractions:
84/216 + 189/216 = 84 + 189/216 = 273/216 - 273/216 simplified gives 91/72
- So, 21/54 + 7/8 = 91/72
In mixed form: 119/72
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