Add 21/45 and 9/20
21/45 + 9/20 is 11/12.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 45 and 20 is 180
Next, find the equivalent fraction of both fractional numbers with denominator 180 - For the 1st fraction, since 45 × 4 = 180,
21/45 = 21 × 4/45 × 4 = 84/180 - Likewise, for the 2nd fraction, since 20 × 9 = 180,
9/20 = 9 × 9/20 × 9 = 81/180 - Add the two like fractions:
84/180 + 81/180 = 84 + 81/180 = 165/180 - 165/180 simplified gives 11/12
- So, 21/45 + 9/20 = 11/12
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