Add 21/18 and 54/45
1st number: 1 3/18, 2nd number: 1 9/45
21/18 + 54/45 is 71/30.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 18 and 45 is 90
Next, find the equivalent fraction of both fractional numbers with denominator 90 - For the 1st fraction, since 18 × 5 = 90,
21/18 = 21 × 5/18 × 5 = 105/90 - Likewise, for the 2nd fraction, since 45 × 2 = 90,
54/45 = 54 × 2/45 × 2 = 108/90 - Add the two like fractions:
105/90 + 108/90 = 105 + 108/90 = 213/90 - 213/90 simplified gives 71/30
- So, 21/18 + 54/45 = 71/30
In mixed form: 211/30
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