Add 21/14 and 81/90
1st number: 1 7/14, 2nd number: 81/90
21/14 + 81/90 is 12/5.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 14 and 90 is 630
Next, find the equivalent fraction of both fractional numbers with denominator 630 - For the 1st fraction, since 14 × 45 = 630,
21/14 = 21 × 45/14 × 45 = 945/630 - Likewise, for the 2nd fraction, since 90 × 7 = 630,
81/90 = 81 × 7/90 × 7 = 567/630 - Add the two like fractions:
945/630 + 567/630 = 945 + 567/630 = 1512/630 - 1512/630 simplified gives 12/5
- So, 21/14 + 81/90 = 12/5
In mixed form: 22/5
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