The correct selling price is $19.98 ($20) and the likely error is that the manager ommited the zero at the back of the 2
Here, we want to find the correct selling price
The markup here is 11%
And the selling price would be $18 + (11% of $18)
Mathematically, that would be;
To the nearest whole dollars, this is a value of $20
So what likely happened here is that the manager ommited the zero at the back of the 32