Answer:
1 standard deviation
Step-by-step explanation:
Given that :
IQs as measured by the Wechsler Adult Intelligence Scale are approximately Normal with:
Mean = 100
Standard deviation = 15
About 84% of people will have IQs below 115 because:
84% = 0.84
From z - table, 0.84 corresponds to a z- score of about 0.995
0.995 = 1. 00
The z-score gives the number of standard deviations by which a raw score is above or below the average or mean value.
Raw score = 115
Mean = 100
Standard deviation (sd) = 15
Mean + number of sd's
100 + 1(sd)
100 + 1(15) = 100 + 15 = 115
SOLUTION:
A normal distribution would model this situation because the distribution is approximately symmetrical, thus the mean, median and mode are approximately the same and the population size is large ( greater than 30).
In algebraic terms this is:
The integer is 2.
Answer:
Solution : (15, - 11)
Step-by-step explanation:
We want to solve this problem using a matrix, so it would be wise to apply Gaussian elimination. Doing so we can start by writing out the matrix of the coefficients, and the solutions ( - 5 and - 2 ) --- ( 1 )
Now let's begin by canceling the leading coefficient in each row, reaching row echelon form, as we desire --- ( 2 )
Row Echelon Form :
Step # 1 : Swap the first and second matrix rows,
Step # 2 : Cancel leading coefficient in row 2 through ,
Now we can continue canceling the leading coefficient in each row, and finally reach the following matrix.
As you can see our solution is x = 15, y = - 11 or (15, - 11).