Homework Answers

The final exam in statistics class were normally distributed with a mean of 63 and standard deviation of 5. Find the 90th percentile

Find the derivative for each function.

1.) y=x^4-3x^3+5x^2-2x+1

2.) y=7/9

Let vector A=a1i +a2j + a3k and B=b1i + b2j + b3k ne on the same plane. Fine the unit vector perpendicular to both A and B.

Find the position vector of the point in space P that lies on the line AB such that |AP|/|PB|= m/n with m, n is a real number. Find the position vector of P if vector A=(1,2,1), B(3,-1,2), m=3 and n=2

Solve for the determinant in the equation below. (10)

 1.7.1. 

4 −3 2

1 2 −2

2 −1 −4

 1.7.2

2 −2 1

2 2 1

4 1 3

As urvey unofficially claimed that in every five young executives, only one practices good reading habits.

What is the probability that out of 10 young executives, two executives practice good reading habits? （b) What is the probability that at least five out of 20 young executives practice good reading habits? 

 If Universal Set U = {90, 91 , 92 , 93 , 94, 95 , 96 , 97 , 98, 99 , 100} (10)

 A = {90, 92, 94, 96, 98, 100}, 

 B= {91, 93, 95, 97, 99}, 

 C = {90, 94, 98}

 1.4.1 What is (A ∩ C)c 

 1.4.2 What is(B ∪ C)c

Three points with position vectors, b and c are said to be colinear. If the parallelogram with adjacent sides a - b and a - c has zero geometry area. Use this fact to check whether or not the following triples of points are collinear

(a) (2,2,3), (6,1,5) (2,4,3)

(b) (2,3,3), (3,7,5), (0,-5,-1)

(c) (1,3,2), (4,2,1), (1,0,2)