Answer: 758
Step-by-step explanation:
Given : Mean : [tex]\mu=6.9 \text{ toys per year][/tex]
Standard deviation : [tex]\sigma = 1.3[/tex]
Margin of error : [tex]E=0.11\text{ toys}[/tex]
Significance level : [tex]\alpha=1-0.98=0.02[/tex]
Critical value : [tex]z_{\alpha/2}=2.33[/tex]
Formula for sample size :-
[tex]n=(\dfrac{z_{\alpha/2}\sigma}{E})^2\\\\\Rightarrow\ n=(\dfrac{2.33\times1.3}{0.11})^2=758.251322314\approx758[/tex]
Hence, the minimum required sample size = 758
