Add 42/90 and 40/81
42/90 + 40/81 is 389/405.
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,
42/90 = 42 × 9/90 × 9 = 378/810 - Likewise, for the 2nd fraction, since 81 × 10 = 810,
40/81 = 40 × 10/81 × 10 = 400/810 - Add the two like fractions:
378/810 + 400/810 = 378 + 400/810 = 778/810 - 778/810 simplified gives 389/405
- So, 42/90 + 40/81 = 389/405
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