Answer:
A. 0.84
Step-by-step explanation:
By the empirical rule, we have the following
Where m is the mean and s is the standard deviation.
In this case, we want to calculate P(x < 53) but
mean + standard deviation = 50 + 3 = 53
So, we need to calculate the probability that it is lower than m + s, so the probability is equal to
P(x < 53) = 0.15% + 2.35% + 13.5% + 34% + 34%
P(x < 53) = 84%
Since 84% = 0.84, we get that the answer is
A. 0.84