Add 21/8 and 45/18
1st number: 2 5/8, 2nd number: 2 9/18
21/8 + 45/18 is 41/8.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 8 and 18 is 72
Next, find the equivalent fraction of both fractional numbers with denominator 72 - For the 1st fraction, since 8 × 9 = 72,
21/8 = 21 × 9/8 × 9 = 189/72 - Likewise, for the 2nd fraction, since 18 × 4 = 72,
45/18 = 45 × 4/18 × 4 = 180/72 - Add the two like fractions:
189/72 + 180/72 = 189 + 180/72 = 369/72 - 369/72 simplified gives 41/8
- So, 21/8 + 45/18 = 41/8
In mixed form: 51/8
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