Answer: in order to qualify, the time must be at least 15.93 minutes
Step-by-step explanation:
Let x be a random variable representing the average response times of fire departments to fire calls. Since it follows a normal distribution, we will determine the z score by applying the formula,
z = (x - µ)/σ
Where
x = sample mean
µ = population mean
σ = population standard deviation
From the information given,
µ = 12.8 minutes
σ = 3.7 minutes
in order to qualify for the special safety award, the probability value would be to the right of the z score corresponding to 80%
The z score corresponding to 80% on the normal distribution table is 0.845
Therefore,
0.845 = (x - 12.8)/3.7
0.845 × 3.7 = x - 12.8
3.13 = x - 12.8
x = 12.8 + 3.13 = 15.93
Answer:
Step-by-step explanation:
Distribute the 1/4:
1/4(16x) + 1/4(20) - 7x
Do the multiplication:
1/4(16x) = 16x/4 = 4x
1/4 (20) = 20/4 = 5
Now you have:
4x + 5 - 7x = 0
Combine like terms (4x and -7x):
-3x + 5 = 0
Subtract 5 from both sides:
-3x = -5
Divide by -3:
x = -5/-3 = 5/3
Answer:
x= 5/3
19 is the answer for this question
