Add 21/28 and 7/8
21/28 + 7/8 is 13/8.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 28 and 8 is 56
Next, find the equivalent fraction of both fractional numbers with denominator 56 - For the 1st fraction, since 28 × 2 = 56,
21/28 = 21 × 2/28 × 2 = 42/56 - Likewise, for the 2nd fraction, since 8 × 7 = 56,
7/8 = 7 × 7/8 × 7 = 49/56 - Add the two like fractions:
42/56 + 49/56 = 42 + 49/56 = 91/56 - 91/56 simplified gives 13/8
- So, 21/28 + 7/8 = 13/8
In mixed form: 15/8
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