Answer: $14.0
Step-by-step explanation:
For us to calculate this question, we have to find 20% of $17.45 and then subtract the value gotten from $17.45. This will be:
= $17.45 - (20% × $17.45)
= $17.45 - (0.2 × $17.45)
= $17.45 - $3.49
= $13.96
= $14.0 to nearest cent
Answer:
The value is 
Step-by-step explanation:
From the question we are told that
The mean is 
The standard deviation is 
The safest water level is between 7.2 and 7.8
Generally the probability that the selected pool has a pH level that is not considered safe is mathematically represented as

Here

Generally 
So
=>
From the z-table the probability of (Z < -1.5) and ( Z <1.5) are

and

So
So

=> 
Answer: The charge was right.
Step-by-step explanation:
If he charged $18 per hour, it means he charged $18 for 60 minutes. He worked for 2 hours 15 minutes which is (60 ×2) + 15 = 135 minutes. For 135 mins, (135 ×18)÷ 60 = 40.5.
He drove 21 miles to his house and 21 miles back. That is 21×2= 42. And for $0.27 = $11.34.
Adding the costs, 40.5 + 11.34 = $51.84