Answer
No, the probability will not be unusual as it is not less than 0.05.
Work Step by Step
p̂ = 450/600 = 0.75
To calculate $P(p̂ \geq 70)$, we need to find the z-score:
$z = \frac{p̂ - μ_{p̂}}{σ_{p̂}}$
$= \frac{.75-.72}{0.0183}$ = 1.64
$P(z \geq 1.64) = 0.0.0505$, hence:
$P(p̂ \geq 0.75) = 0.0505$
