Add 21/30 and 45/18
1st number: 21/30, 2nd number: 2 9/18
21/30 + 45/18 is 16/5.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 30 and 18 is 90
Next, find the equivalent fraction of both fractional numbers with denominator 90 - For the 1st fraction, since 30 × 3 = 90,
21/30 = 21 × 3/30 × 3 = 63/90 - Likewise, for the 2nd fraction, since 18 × 5 = 90,
45/18 = 45 × 5/18 × 5 = 225/90 - Add the two like fractions:
63/90 + 225/90 = 63 + 225/90 = 288/90 - 288/90 simplified gives 16/5
- So, 21/30 + 45/18 = 16/5
In mixed form: 31/5
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