At a college the scores on the chemistry final exam are approximately normally distributed, with a mean of 77 and a standard deviation of 10. The scores on the calculus final are also approximately normally distributed, with a mean of 83 and a standard deviation of 14. A student scored 81 on the chemistry final and 81 on the calculus final. Relative to the students in each respective class, in which subject did the student do better?

Student do better in Chemistry subject.

Step-by-step explanation:

We are given that at a college the scores on the chemistry final exam are approximately normally distributed, with a mean of 77 and a standard deviation of 10. The scores on the calculus final are also approximately normally distributed, with a mean of 83 and a standard deviation of 14.

A student scored 81 on the chemistry final and 81 on the calculus final.

And we have to find that  in which subject did the student do better.

Firstly, Let X = scores on the chemistry final exam

So, X ~ N()

Also, let Y = scores on the calculus final exam

So, Y ~ N()

For finding in which subject did the student do better, we will find the z score for both the exams of student because the higher the z score, the better is the student perform in that exam.

The z-score probability distribution is given by;

              Z = ~ N(0,1)

where, = mean score for respective subjects

            = standard deviation

Since we are given the student score of 81 on the chemistry final exam,

So,  z-score = = 0.4  {where and }

Since we are given the student score of 81 on the calculus final exam,

So,  z-score = = -0.143     {where and }

AS we can clearly see that the z score of Chemistry final exam is higher than that of Calculus exam so the student do better in Chemistry subject exam.

answer: 180

step-by-step explanation:

12-2=10

20-2=18

10x18=180

i believe the answer is letter c) 8

step-by-step explanation: