Add 21/20 and 54/45
1st number: 1 1/20, 2nd number: 1 9/45
21/20 + 54/45 is 9/4.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 20 and 45 is 180
Next, find the equivalent fraction of both fractional numbers with denominator 180 - For the 1st fraction, since 20 × 9 = 180,
21/20 = 21 × 9/20 × 9 = 189/180 - Likewise, for the 2nd fraction, since 45 × 4 = 180,
54/45 = 54 × 4/45 × 4 = 216/180 - Add the two like fractions:
189/180 + 216/180 = 189 + 216/180 = 405/180 - 405/180 simplified gives 9/4
- So, 21/20 + 54/45 = 9/4
In mixed form: 21/4
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