Add 21/30 and 9/18
21/30 + 9/18 is 6/5.
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,
9/18 = 9 × 5/18 × 5 = 45/90 - Add the two like fractions:
63/90 + 45/90 = 63 + 45/90 = 108/90 - 108/90 simplified gives 6/5
- So, 21/30 + 9/18 = 6/5
In mixed form: 11/5
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