Add 20/40 and 42/81
20/40 + 42/81 is 55/54.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 40 and 81 is 3240
Next, find the equivalent fraction of both fractional numbers with denominator 3240 - For the 1st fraction, since 40 × 81 = 3240,
20/40 = 20 × 81/40 × 81 = 1620/3240 - Likewise, for the 2nd fraction, since 81 × 40 = 3240,
42/81 = 42 × 40/81 × 40 = 1680/3240 - Add the two like fractions:
1620/3240 + 1680/3240 = 1620 + 1680/3240 = 3300/3240 - 3300/3240 simplified gives 55/54
- So, 20/40 + 42/81 = 55/54
In mixed form: 11/54
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