Answer:
The value of "x" is 5.
Step-by-step explanation:
In order to solve this system of equations, we first have to take the first equation and use it to represent "y" in terms of "x". We do that in the following way...
Now, we need to take the second equation and substitute "y" for the equivalent value in terms of "x". After doing this we will get the following equation, which we can solve to get the value of "x".
Therefore, the value of "x" is 5.
Let x represent the scores. With mean and standard deviation given,
The Empirical rule states that
1) About 68% of the x values lie between 1 standard deviation below and above the mean
2) About 95% of the x values lie between 2 standard deviation below and above the mean
3) About 99.7% of the x values lie between 3 standard deviation below and above the mean
If we consider this rule, then the percentage of scores that fall within 3 standard deviation (-3 to +3) is 99% because this is closer to 99.7%
