So you have to plug in the amount to the cost making you problem look like this:
0.85(30)+2.5(2)
25.5+5=30.5
Answer:
a = 4
Step-by-step explanation:
Given equation:
4a - 5 = 11
Add 5 to both sides:
⇒ 4a - 5 + 5 = 11 + 5
⇒ 4a = 16
Divide both sides by 4:
⇒ 4a ÷ 4 = 16 ÷ 4
⇒ a = 4
Answer:
Step-by-step explanation:
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Hope this helped!
<h3>~AH1807</h3><h3>Peace!</h3>
Answer:
Step-by-step explanation:
Since the length of time taken on the SAT for a group of students is normally distributed, we would apply the formula for normal distribution which is expressed as
z = (x - u)/s
Where
x = length of time
u = mean time
s = standard deviation
From the information given,
u = 2.5 hours
s = 0.25 hours
We want to find the probability that the sample mean is between two hours and three hours.. It is expressed as
P(2 lesser than or equal to x lesser than or equal to 3)
For x = 2,
z = (2 - 2.5)/0.25 = - 2
Looking at the normal distribution table, the probability corresponding to the z score is 0.02275
For x = 3,
z = (3 - 2.5)/0.25 = 2
Looking at the normal distribution table, the probability corresponding to the z score is 0.97725
P(2 lesser than or equal to x lesser than or equal to 3)
= 0.97725 - 0.02275 = 0.9545
