The grocer prepared total 110 samples.
Explanation
Suppose, the total number of samples the grocer prepared is [tex]x[/tex]
By lunchtime, the grocer has given out 5 fewer than half the total number of samples. So, the number of samples given out by lunchtime [tex]= \frac{1}{2}x -5[/tex]
Now, it is given that she gives out 50 samples before lunch. That means...
[tex]\frac{1}{2}x -5 =50\\ \\ \frac{1}{2}x=5+50\\ \\ \frac{1}{2}x=55\\ \\ x=55*2=110[/tex]
So, the total number of samples the grocer prepared is 110.