Add 21/16 and 20/90
1st number: 1 5/16, 2nd number: 20/90
21/16 + 20/90 is 221/144.
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,
20/90 = 20 × 8/90 × 8 = 160/720 - Add the two like fractions:
945/720 + 160/720 = 945 + 160/720 = 1105/720 - 1105/720 simplified gives 221/144
- So, 21/16 + 20/90 = 221/144
In mixed form: 177/144
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