hello,
define the null hypothesis : μ = 269.3
Alternative hypothesis :μ>269.3
here the sample size is small so we can use t statistic for single mean:
thus t = (sample mean - population mean)/s.d/√n
thus t = (267.3 - 269.3)/0.632/√25
= -15.82
the table value of t at (25-1) 24 degrees of freedom and at 5% level of significance is 1.71
since the calculated value is less than the table value.
hence we accept null hypothesis
that is the claim is not true
hope this will help yo