Add 81/90 and 42/81
81/90 + 42/81 is 383/270.
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,
81/90 = 81 × 9/90 × 9 = 729/810 - Likewise, for the 2nd fraction, since 81 × 10 = 810,
42/81 = 42 × 10/81 × 10 = 420/810 - Add the two like fractions:
729/810 + 420/810 = 729 + 420/810 = 1149/810 - 1149/810 simplified gives 383/270
- So, 81/90 + 42/81 = 383/270
In mixed form: 1113/270
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