Add 18/3 and 45/21
1st number: 6 0/3, 2nd number: 2 3/21
18/3 + 45/21 is 57/7.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 3 and 21 is 21
Next, find the equivalent fraction of both fractional numbers with denominator 21 - For the 1st fraction, since 3 × 7 = 21,
18/3 = 18 × 7/3 × 7 = 126/21 - Likewise, for the 2nd fraction, since 21 × 1 = 21,
45/21 = 45 × 1/21 × 1 = 45/21 - Add the two like fractions:
126/21 + 45/21 = 126 + 45/21 = 171/21 - 171/21 simplified gives 57/7
- So, 18/3 + 45/21 = 57/7
In mixed form: 81/7
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