Answer:
102.4?
Step-by-step explanation:
Answer:
x = 1 1/4
Step-by-step explanation:
sqrt( 7x+2) = sqrt(3x+7)
Square each side
(sqrt( 7x+2))^2 = (sqrt(3x+7))^2
7x+2 = 3x+7
Subtract 3x from each side
7x-3x +2 = 3x+7-3x
4x+2 = 7
Subtract 2 from each side
4x+2-2 = 7-2
4x = 5
Divide by 4
4x/4 = 5/4
x = 1 1/4
Check for extraneous solution
sqrt( 7*5/4+2) = sqrt(3*5/4+7)
sqrt( 35/4 + 8/4) = sqrt(15/4+28/4)
sqrt( 43/4) = sqrt(43/4)
Solution is valid
Answer:
1
Step-by-step explanation:
There are about 110,000 days in 300 years, so the expected number of failures is about 10/11 ≈ 1.
_____
This assumes the launch conditions are identical for each of the launches, or that whatever variation there might be has no effect on the probability. These are bad assumptions.
Answer:

Step-by-step explanation:
Distribute the 4

Subtract the 7

Subtract y and add 1
Answer: 0.6827
Step-by-step explanation:
Given : Mean IQ score : 
Standard deviation : 
We assume that adults have IQ scores that are normally distributed .
Let x be the random variable that represents the IQ score of adults .
z-score : 
For x= 90

For x= 120

By using the standard normal distribution table , we have
The p-value : 

Hence, the probability that a randomly selected adult has an IQ between 90 and 120 =0.6827