Add 21/4 and 81/90
1st number: 5 1/4, 2nd number: 81/90
21/4 + 81/90 is 123/20.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 4 and 90 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 90 × 2 = 180,
81/90 = 81 × 2/90 × 2 = 162/180 - Add the two like fractions:
945/180 + 162/180 = 945 + 162/180 = 1107/180 - 1107/180 simplified gives 123/20
- So, 21/4 + 81/90 = 123/20
In mixed form: 63/20
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