Add 21/45 and 15/20
21/45 + 15/20 is 73/60.
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,
15/20 = 15 × 9/20 × 9 = 135/180 - Add the two like fractions:
84/180 + 135/180 = 84 + 135/180 = 219/180 - 219/180 simplified gives 73/60
- So, 21/45 + 15/20 = 73/60
In mixed form: 113/60
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