A senator claims that 80% of her constituents favour her voting policies over t

A senator claims that 80% of her constituents favour her voting policies over t

A senator claims that 80% of her constituents favour her voting policies over the past year.
In a random sample of 50 of these people, the sample proportion of those favoured her voting policies was only 0.5. Is this enough evidence to make the senator’s claims strongly suspect? (Hint: Use a normal approximation to the binomial distribution then construct a confidence interval)