In the coordinate plane a slope of the line K is 4 times the y-intercept of the line K. What is the x-intercept of the line K? A. -4 B. 4 C. -1/4 D. 1/4 E. 2 ANS: As Y=4mx+m, from 0=4mx+m we get x=-1/4. Hence, the correct answer choice is C.

Which of the following are roots of an equation (x^-2)+(2x^-1)-15=0 A. 1/5 and -1/3 B. -1/5 and 1/3 C. 1/5 and 1/3 D. -1/5 and -1/3 E. -5/2 and -1/3 *ANS: If we multiply both sides by x^2, we get 1+2x-15x^2=0, (15x^2)-2x-1=0, (3x-1)(5x+1)=0. Hence, x=1/3 or -1/5, and the correct answer is B.

There are 7 red balls and 5 blue balls in a jar. If 3 balls are selected from the jar, what is the probability that 3 balls selected are red balls? A. 19/44 B. 5/44 C. 3/41 D. 13/44 E. 7/44 *ANS: From 7C3/12C3=7/44, the correct answer is E.

If a=-1, which of the following is(are) true? I. a^a=-|a| II. a^0=-a^-1 III. |a|=a A. I only B. II only C. III only D. I & II only E. I , II & III only *ANS: From (-1)0=1, (-1)-1=-1, |-1|=1, the correct answer is D.

Which of the following points is symmetric with y=x at (-1,-2)? A. (-2,-1) B. (-2,1) C. (2,1) D. (-1,-2) E. (-1,2) ANS: If the point is symmetric to y=x, we can put y-value to x coordinates and put x-value into y coordinates. Then we get (-1, -2) --> (-2, -1). Hence, the correct answer is A.

If (n+2)!/n!=132, n=? A. 2/131 B. 9 C. 10 D. 11 E. 12 ANS: (n+2)!/n!=(n+2)(n+1)n!/n!=(n+2)(n+1)=132, n^2+3n-130=0, (n+12)(n-10)=0. Hence, the correct answer is C.

If x=(10^10)-47, what is the sum of all the digit of x? A. 40 B. 45 C. 50 D. 55 E. 80 *ANS: From (10^10)-47=9,999,999,953, the sum of all digit is 9(8)+6+2=80. The answer is E.

How many factors of 330 are odd numbers greater than 1? A. 3 B. 4 C. 5 D. 6 E. 7 ANS: If we calculate, we get 330=2*3*5*11. We are trying to find odd factors. So we have to find 3*5*11. From (1+1)(1+1)(1+1)=8, we only have to get rid of 1. The answer is 7. Hence, the correct answer is E.

If ABCD is a square with its side length is 10ft and points P, Q, M are midpoints of AD, AB, and BC, respectively, what is the area of region shaded as above figure? A. 40 B. 45 C. 50 D. 75/2 E. 33 ANS: The area of a triangle CDM is 25 and the area of a triangle APO is 25/2. The sum of areas is 25+(25/2)=75/2. Hence, the correct answer is D.

Which of the following is closest to (-3/4)^199？ A. -1 B. -1/2 C. 0 D. 1 E. 2 ANS: From -1<x<1, x^n approaches 0 as n increases. Hence, the correct answer is C.

If x, 1, 2, 3 are there and the range and median of them are the same, what is the value of x? A. 0 B. 1 C. 2 D. 3 E. 4 ANS: If x=2, then from 1,2,2,3, the range becomes range=3-1=2=median. Hence, the correct answer is C.