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
3 1 10
------ + --------------- = ----------
3x x +4 7x
1 1 10
------ + ------------ = ----------
x x +4 7x
x + 4 + x 10
------------------ = ----------
x(x +4) 7x
2x + 4 10
------------------ = ----------
x(x +4) 7x
7x(2x + 4) = 10x(x+4)
14x^2 + 28x = 10x^2 + 40x
4x^2 - 12x = 0
4x(x - 3) = 0
4x = 0
x = 0
x - 3 = 0
x = 3
answer x = 0 and x = 3
Answer:
420
Step-by-step explanation:
20 percent of 350 is 70, so adding that on will give us the price it is sold at for profit of 70 (20%).
The diameter of the pool cover in one hundred feet
