Add 21/90 and 9/10
21/90 + 9/10 is 17/15.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 90 and 10 is 90
Next, find the equivalent fraction of both fractional numbers with denominator 90 - For the 1st fraction, since 90 × 1 = 90,
21/90 = 21 × 1/90 × 1 = 21/90 - Likewise, for the 2nd fraction, since 10 × 9 = 90,
9/10 = 9 × 9/10 × 9 = 81/90 - Add the two like fractions:
21/90 + 81/90 = 21 + 81/90 = 102/90 - 102/90 simplified gives 17/15
- So, 21/90 + 9/10 = 17/15
In mixed form: 12/15
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