Add 21/28 and 9/8
1st number: 21/28, 2nd number: 1 1/8
21/28 + 9/8 is 15/8.
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,
9/8 = 9 × 7/8 × 7 = 63/56 - Add the two like fractions:
42/56 + 63/56 = 42 + 63/56 = 105/56 - 105/56 simplified gives 15/8
- So, 21/28 + 9/8 = 15/8
In mixed form: 17/8
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