A score of 85 would be 1 standard deviation from the mean, 74. Using the 68-95-99.7 rule, we know that 68% of normally distributed data falls within 1 standard deviation of the mean. This means that 100%-68% = 32% of the data is either higher or lower. 32/2 = 16% of the data will be higher than 1 standard deviation from the mean and 16% of the data will be lower than 1 standard deviation from the mean. This means that 16% of the graduating seniors should have a score above 85%.
Answer:
- The two solutions are:
- The next and every step are below.
Explanation:
1. 
: Given (addition property / add - 3 to both sides)
2. 
: Given (commom factor - 2)
3. 
To obtain the perfect square it was added the square of half of the coefficient of x: (1/2)² = 1/4, inside the parenthesis.
Since, the terms inside the parentthesis are multiplied by - 2, you have to add - 2 (1/4) = - 1/2 to the left side of the equation.
4. Now, you have that the trinomial x² - x + 1/4 is a square perfect trinomial which is factored as (x - 1/2)² and get the expression:
5. Divide both sides by - 2 to get the next expression:
6. The last step is to extract squere root from both sides of the equality:
f(3) is equal to -101.
<u>Step-by-step explanation</u>:
- The sequence is followed by f(0)=4
- The given expression is f(n+1)= -3f(n)+1
Put n=0,
f(0+1)= -3f(0)+1
f(1)= -3(4)+1
f(1)= -12+1 = -11
Put n=1,
f(1+1)= -3f(1)+1
f(2)= -3(-11)+1
f(2)= 33+1 = 34
Put n=2,
f(2+1)= -3f(2)+1
f(3)= -3(34)+1
f(3)= -102+1
f(3)= -101
