It belongs to rational numbers, hope this helps!
Answer:
2.5% of IQ scores are no more than 65
Step-by-step explanation:
The Empirical Rule states that, for a normally distributed random variable:
68% of the measures are within 1 standard deviation of the mean.
95% of the measures are within 2 standard deviation of the mean.
99.7% of the measures are within 3 standard deviations of the mean.
In this problem, we have that:
Mean = 95
Standard deviation = 15
Using the empirical rule, what percentage of IQ scores are no more than 65?
65 = 95 - 2*15
So 65 is two standard deviations below the mean.
By the Empirical Rule, 95% of the measures are within 2 standard deviation of the mean. Of those 5% which are not, 2.5% are more than 2 standard deviations above the mean and 2.5% are more than 2 standard deviations below the mean.
So 2.5% of IQ scores are no more than 65
Answer: y = -5x+5
Step-by-step explanation: Slope intercept form is written as y = mx+b where m is the slope of the function and b is the y-intercept of the function. In this linear function, the line crosses the y-axis at (0,5). This is the y-intercept. We can find the slope with the (y2 - y1) / (x2 - x1) by choosing 2 points on the graph. I chose (0,5) and (1,0). If you use the formula, you will end up with -5 as your slope.
Answer:
90% confidence interval for the mean is between a lower limit of 3.08 days and an upper limit of 3.18 days.
Step-by-step explanation:
Confidence interval is given as mean +/- margin of error (E)
mean = 3.13 days
sd = 0.48 day
n = 250
degree of freedom = n-1 = 250-1 = 249
confidence level (C) = 90% = 0.9
significance level = 1 - C = 1 - 0.9 = 0.1 = 10%
critical value (t) corresponding to 249 degrees of freedom and 10% significance level is 1.65153
E = t×sd/√n = 1.65153×0.48/√250 = 0.05 day
Lower limit of mean = mean - E = 3.13 - 0.05 = 3.08 days
Upper limit of mean = mean + E = 3.13 + 0.05 = 3.18 days
90% confidence interval is (3.08, 3.18)
Answer: 4/5 of 45 is 36
Step-by-step explanation: If you were to divide 45 by 5 you would get 9. 9 is 1/5 of 45 so if you multiplied it by 4 you would 4/5 of 45 which is 36.