Answer:
The last one
Step-by-step explanation:
Since we cannot be 100% sure which test Frank did better on, we need to find a way to make the comparison doable. This can be done by converting Frank's score to the
standard score (or also known as the z-score).
The z-score is calculated through the following formula:

where X is Frank's original score.
Converting Frank's scores to a standard score accounting for both the mean and standard deviation of the population who took the test will make the comparison possible.
We get the following z-scores after conversion:


If you read up more on the concept of z-score, you may know that this score just means the amount of standard deviations a data falls with respect to the mean. Comparing Frank's two scores, we can see that they are both below the mean. However, it can be seen that Frank's z-score for his chemistry test is lower than his z-score for his biology test.
This suggests that Frank scored relatively poorer in chemistry than he did in biology.
ANSWER: Frank did better in his biology test.
Answer:
f(x) = - 3x + 4
Step-by-step explanation:
Given
9x + 3y = 12 ← rearrange making y the subject
Subtract 9x from both sides
3y = - 9x + 12 ( divide all terms by 3 )
y = - 3x + 4, or in functional notation as
f(x) = - 3x + 4
Answer:
p - 3
Step-by-step explanation:
"fewer than" means subtract from, in this case 3, from an unknown number represented by p
Answer:
p(x) = 7/5 x + 5.
Step-by-step explanation:
The slope of the function = difference in values / f(x) / difference in values of x
= (19-12) / (10 - 5) = 7/5
also:
(26-19) / ( 15 - 10) = 7/5
and (33-26) / (20-15) = 7/5.