The cost of the trip is $150
First, we need to subtract the money he already saved from the cost of the trip
150-26=124
so we need to save $124 in 8 months
[tex]\frac{124}{8}=15.5[/tex]She needs to save $15.5 each month
In an equation
26+8x=150
where x is the money that she needs to save each month
we need to clear x
[tex]\begin{gathered} 8x=150-26 \\ 8x=124 \\ x=\frac{124}{8} \\ x=15.5 \end{gathered}[/tex]