Question 1171769
point estimate is 450/900 =0.5. Can use normal distribution here because np and n(1-p) are both > 10.
Ho: proportion is 0.60
Ha: proportion is not 0.60
let alpha be 0.05 p{reject Ho|Ho true}
test is z for a 1 sample proportion 
critical value is |z| > 1.96
z=(p hat-p)/sqrt(0.6*0.4/900)
=-0.10/.0.0163
=-6.12
strongly reject Ho, and it is not 60% of their members like their jobs.