Question 13 is 14 x is 14
She should use a computer to select 30 students at random then ask which ones play chess. The other options could produce more skewed results.
16% percent of the students paid MORE than Jane.
The mean(μ) of money spent on textbooks is 500
The standard deviation(σ) of money spent on textbooks is 50
Money paid by Jane for her books is $550
We will use this formula,
Ζ=x-μ/σ
To find: the percentage of students paid MORE than Jane for the textbooks
=?
Solution:
≤
=
Ζ≤
=1-P(Ζ≤ 1)
=1-0.8413
=0.1587
≈16%
Therefore, 16% percent (approx) of the students paid MORE than Jane.
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Answer:
Step-by-step explanation:
Let c represent the number of children that attended the concert.
Let a represent the number of adults that attended the concert.
At one of the concerts, each adult brought 4 children with them, and 10 children attended without an adult. This means that the number of children that attended is
c = 4a + 10
Tickets for a concert were $5 for each child and $8 for each adult. The total ticket sales were $1730. It means that
5c + 8a = 1730
Therefore, the systems of equations that can be solved to determine the number of children, c, and adults that attended the concert is
c = 4a + 10
5c + 8a = 1730