Answer: The value of the test statistic is z= 1.63 .
Explanation:
Test statistic for proportion :

, where p =population proportion.
= sample proportion
n= sample size.
Let p be the proportion of chips do not fail in the first 1000 hours of their use.
As per given, we have

Then, required test statistic would be

Hence, the value of the test statistic is z= 1.63 .