Answer:
a level of significance of 0.01 = 1%
Step-by-step explanation:
given
Z = 0.0001
mean μ=0.21 g/mi
variate x= 0.21 + 0.03
standard deviation σ= 0.05 g/mi.
N = sample population 20 cars
z = (x −μ )/[σ /√N ]
Z =
Z = 0.03/ (0.05/√20) = 0.03/0.0111
Z = 2.63 +- 0.0001
Z= 2.6301 or 2.6299
checking the level of significance table from a statistical book gives
a level of significance of 0.01 = 1%
therefore the null hypothesis is accepted.