Answer:
92
Explanations:
Average number of days used by the batteries = 101
Margin error = 9%
![\begin{gathered} \text{Margin error = }(9)/(100)*101 \\ \text{Margin error = }9.09 \end{gathered}](https://img.qammunity.org/2023/formulas/mathematics/college/pvmodwfsat90bylouft0oyl8lvxpntpsmi.png)
Minimum average number of days = 101 - Margin error
Minimum average number of days = 101 - 9.09
Minimum average number of days = 91.91
Minimum average number of days = 92 ( to the nearest whole number)