The number of yellows counter is given by the function:
[tex]f(n)=128-\frac{1}{2}n[/tex]if we want this to be exactly 1 counter we equate the function to 1 and solve for n:
[tex]\begin{gathered} 128-\frac{1}{2}n=1 \\ 128-1=\frac{1}{2}n \\ \frac{1}{2}n=127 \\ n=127\cdot2 \\ n=254 \end{gathered}[/tex]Therefore, the number of trials will be 254.
