Answer:
16%
Step-by-step explanation:
The mean is $15 and the standar deviation is $3.
mean = 15 and SD = 3
We need to find percentage less than 12 per hour
P(x<12)= P(x=12)
to find P(x=12) we find z-score
Now use z-score table . z-score = 0.1587
P(x=12)=0.1587
To get percentage we multiply by 100
0.1587 * 100 = 15.87 = 16%