Ling tried to solve an equation step by step.
\qquad\begin{aligned} -2q+11&=-32 \\ -2q&=-43&\green{\text{Step } 1} \\ q&=21.5&\blue{\text{Step } 2} \end{aligned}
−2q+11
−2q
q


=−32
=−43
=21.5


Step 1
Step 2


Find Ling's mistake.

According to a study conducted in 2015, 18% of shoppers said that they prefer to buy generic instead of name-brand products. suppose that in a recent sample of 1500 shoppers, 315 stated that they prefer to buy generic instead of name-brand products. at a 5% significance level, can you conclude that the proportion of all shoppers who currently prefer to buy generic instead of name-brand products is higher than .18? use both the p-value and the critical-value approaches.