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%
Answer:
Standard error = 0.4
Step-by-step explanation:
Step 1
We find the Standard Deviation
The formula = √(x - mean)/n - 1
n = 15
Mean = 1.93 hours
= √(0- 1.93)² + (0-1.93)² +(0- 1.93)²+( 0- 1.93)²+ (1- 1.93)² + (1- 1.93)² +(1 - 1.93)² +(2 - 1.93)² + (2 - 1.93)² + (2 - 1.93)² + (2 - 1.93)² + ( 2 - 1.93)² +(4 - 1.93)² +(4 - 1.93)² + (5 - 1.93)²/15 - 1
= √(3.737777776 + 3.737777776 + 3.737777776 + 0.871111111 +0.871111111 + 0.871111111 + 0.004444444445+ 0.004444444445 + 0.004444444445 + 0.004444444445 + 0.004444444445 + 1.137777778 + 4.271111112 + 4.271111112 + 9.404444446)/15 - 1
= √2.352380952
= 1.533747356
Step 2
We find the standard error
The formula = Standard Deviation/√n
Standard deviation = 1.533747356
n = 15
= 1.533747356/√15
= 1.533747356 /3.87298334621
= 0.39601186447
Approximately = 0.4
Therefore, the standard error is 0.4
Answer:
The first option in the first picture
Step-by-step explanation:
Good luck with summer school bud :)
<u><em>Answer:</em></u>
168
<u><em>Explanation:</em></u>
<u>Before we begin, remember the following:</u>
+ve * +ve = +ve -ve * -ve = +ve
+ve * -ve = -ve -ve * +ve = +ve
<u>Now, for the given problem we have:</u>
(-4) * (6) * (-7)
<u>Let's take the first two terms:</u>
(-4) * (6)
Based on the above rules, the product will be negative
<u>Therefore, </u>
(-4) * (6) = -24
<u>Now, the expression became:</u>
(-24) * (-7)
Again, based on the above rule, the product here will be positive
<u>Therefore,</u>
(-24) * (-7) = 168
Hope this helps :)
