Add 21/16 and 18/90
1st number: 1 5/16, 2nd number: 18/90
21/16 + 18/90 is 121/80.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 16 and 90 is 720
Next, find the equivalent fraction of both fractional numbers with denominator 720 - For the 1st fraction, since 16 × 45 = 720,
21/16 = 21 × 45/16 × 45 = 945/720 - Likewise, for the 2nd fraction, since 90 × 8 = 720,
18/90 = 18 × 8/90 × 8 = 144/720 - Add the two like fractions:
945/720 + 144/720 = 945 + 144/720 = 1089/720 - 1089/720 simplified gives 121/80
- So, 21/16 + 18/90 = 121/80
In mixed form: 141/80
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