Add 21/45 and 12/18
21/45 + 12/18 is 17/15.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 45 and 18 is 90
Next, find the equivalent fraction of both fractional numbers with denominator 90 - For the 1st fraction, since 45 × 2 = 90,
21/45 = 21 × 2/45 × 2 = 42/90 - Likewise, for the 2nd fraction, since 18 × 5 = 90,
12/18 = 12 × 5/18 × 5 = 60/90 - Add the two like fractions:
42/90 + 60/90 = 42 + 60/90 = 102/90 - 102/90 simplified gives 17/15
- So, 21/45 + 12/18 = 17/15
In mixed form: 12/15
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