Add 28/40 and 45/81
28/40 + 45/81 is 113/90.
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,
28/40 = 28 × 81/40 × 81 = 2268/3240 - Likewise, for the 2nd fraction, since 81 × 40 = 3240,
45/81 = 45 × 40/81 × 40 = 1800/3240 - Add the two like fractions:
2268/3240 + 1800/3240 = 2268 + 1800/3240 = 4068/3240 - 4068/3240 simplified gives 113/90
- So, 28/40 + 45/81 = 113/90
In mixed form: 123/90
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