Add 21/4 and 54/45
1st number: 5 1/4, 2nd number: 1 9/45
21/4 + 54/45 is 129/20.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 4 and 45 is 180
Next, find the equivalent fraction of both fractional numbers with denominator 180 - For the 1st fraction, since 4 × 45 = 180,
21/4 = 21 × 45/4 × 45 = 945/180 - Likewise, for the 2nd fraction, since 45 × 4 = 180,
54/45 = 54 × 4/45 × 4 = 216/180 - Add the two like fractions:
945/180 + 216/180 = 945 + 216/180 = 1161/180 - 1161/180 simplified gives 129/20
- So, 21/4 + 54/45 = 129/20
In mixed form: 69/20
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