Answer
$49.85\%$
Work Step by Step
$\text{z-score}=\frac{\text{data item-mean}}{\text{standard deviation}}$
$|\frac{45-29}{4}|=3$, thus these are half the elements that are $3$ standard deviations away from the mean.
The normal distribution is symmetric about the mean. Thus using the 68-95-99.7 rule and the graph we get:
$P(\overline{x}\leq x\leq\overline{x}+3\sigma)=34\%+13.5\%+2.35\%=49.85\%$
