Question

The admissions office of a college wants to determine whether there is a relationship between IQ scores x and grade-point averages y after the first y

Modeling data distributions
ANSWERED
asked 2021-02-09
The admissions office of a college wants to determine whether there is a relationship between IQ scores x and grade-point averages y after the first year of school. An equation that models the data obtained by the admissions office is
\(\displaystyle{y}={0.069}{x}-{4.755}.\)
Estimate the values of x that predict a grade-point average of at least 3.5. (Simplify your answer completely. Round your answer to the nearest whole number.)

Answers (1)

2021-02-10
The given equation modeling the relationship between IQ score and grade point averages is as follows
\(\displaystyle{y}={0.069}{x}-{4.755}\)…(1)
Where y represents grade point averages
And x represents IQ score
We need to find value of x for \(\displaystyle{y}={3.5}\) So substituting \(\displaystyle{y}={3.5}\) in equation (1), we get \(\displaystyle{3.5}={0.069}{x}-{4.755}\)
On simplifying the above equation
\(\displaystyle{0.069}{x}={3.5}+{4.755}\)
\(\displaystyle{0.069}{x}={8.255}\)
\(\displaystyle{x}=\frac{8.255}{{0.069}}\)
\(\displaystyle{x}={119.63}\)
So the next whole number is 120. Hence for IQ score that` is \(\displaystyle{x}={120}\), the grade point average will be at least 3.5.
Answer: For grade point average of at least 3.5 required IQ score is 120
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