Add 21/15 and 81/90
1st number: 1 6/15, 2nd number: 81/90
21/15 + 81/90 is 23/10.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 15 and 90 is 90
Next, find the equivalent fraction of both fractional numbers with denominator 90 - For the 1st fraction, since 15 × 6 = 90,
21/15 = 21 × 6/15 × 6 = 126/90 - Likewise, for the 2nd fraction, since 90 × 1 = 90,
81/90 = 81 × 1/90 × 1 = 81/90 - Add the two like fractions:
126/90 + 81/90 = 126 + 81/90 = 207/90 - 207/90 simplified gives 23/10
- So, 21/15 + 81/90 = 23/10
In mixed form: 23/10
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