Fact
75%
What is the percentage that The NewYork Times claims that people color their hair?
40%
Explain a difference between a statistic and a parameter
Statistic, a measurement that describes a sample
Parameter, a value that that describes a population
How many percents of the world's population is blond?
2%
One proportion Z test
A coin has p=0.6 of turning up heads. Toss the coin 3 times and let X be the count of heads among the 3 coins. What is the probability that we will get 2 heads and 1 tail?
0.6 x 0.6 x 0.4 = 0.432
How much weight can a single strand of hair support?
6.5lbs
2.95kg
What is the Z-value in the project?
0.8642
A summary for a set of data is 52,55,60,63,85. Is the mean most likely to be less than or greater than the median
Mean to be larger than the median due to 85 as our outlier
1mm for every 3 days
0.333 for each day
Out of 27, how many people have non-dyed hair?
14
The correlation between the first and the second statistic test in a class is 0.78. Interpret this value
there is a moderate to strong positive linear relationship between the scores on the first and second tests
What's the rarest hair color
How many people in Block A have dyed hair?
7
Let X be a binomial random variable with n = 250 and p = 0.6. Use the normal approximation to the binomial to approximate P(X>160)
u(x) = 250 x 0.6 = 150
o(x)= square root of (250 x .6 x .4) = 7.75
P (X>160) = P ( z > (160-150)/ 7.75 ) = 0.099