Start with

Add 2x to both sides:

Subtract 21 from both sides:

Divide both sides by 5. Since it is positive, we don't have to change the inequality sign:

So, the answer is 
Answer: 0.82
Step-by-step explanation:
We know that :
For any event A , the probability of not getting A is given by :-
P(not A)= 1- P(A)
Given : The probability that a student chosen at random from your class is a psychology major is P( psychology major) =0.18.
Then, the probability that a student chosen at random from your class is not a psychology major will be :
P(not psychology major)= 1 - P(psychology major)
= 1-0.18=0.82
Hence, the probability that a student chosen at random from your class is not a psychology major= 0.82
Answer:
The 99% confidence interval is
Step-by-step explanation:
From the question we are told that
The sample size is n = 100
The sample mean is 
The population standard deviation is
From the question we are told the confidence level is 99% , hence the level of significance is
=>
Generally from the normal distribution table the critical value of
is
Generally the margin of error is mathematically represented as

=>
Generally 95% confidence interval is mathematically represented as
=>
=>
To solve 7-2a-5-14=-2+3a :
1) combine like terms: 7-19 - 2a = -2 + 3a, and then -10 = 5a
2) solve this equation for a: a = -10/5 = -2.
The solution of 7-2a-5-14=-2+3a is a = -2.
Bell is the tallest person at 52 inches, Con is the shortest person at 42 inches. So 54 - 42 = 12