Add 12/90 and 21/81
12/90 + 21/81 is 53/135.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 90 and 81 is 810
Next, find the equivalent fraction of both fractional numbers with denominator 810 - For the 1st fraction, since 90 × 9 = 810,
12/90 = 12 × 9/90 × 9 = 108/810 - Likewise, for the 2nd fraction, since 81 × 10 = 810,
21/81 = 21 × 10/81 × 10 = 210/810 - Add the two like fractions:
108/810 + 210/810 = 108 + 210/810 = 318/810 - 318/810 simplified gives 53/135
- So, 12/90 + 21/81 = 53/135
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