Help with these Math questions

Celita
Sat, 24 Nov 2007 19:11:17 +0000

The least and greatest numbers in a list of 7 real numbers are 2 and 20, respectively. THe median of the list is 6 and the number 3 occurs most often in the list. Which of the following could be the average of the numbers in the list?


I. 7
II. 8.5
III. 10

A. I Only
B. I and II only
C. I and III only
D. II and III only
E. I, II, and III



2.

The number n is a 2-digit number. When n is divided by 10, the remainder is 9, and when n is divided by 9, the remainder is 8. What is the value of n?



If j is chosen at random from the set {4, 5, 6} and k is chosen at random from the set {10, 11, 12}, what is the probability that the product of j and k is divisible by 5?




http://img.■■■■■■■■■■■■■■■/albums/v289/Amirsan/problem15.jpg




5.

If y=2x+3 and x < 2, which of the following represents all the possible values for y?

A. y < 7
B. y > 7
C. y < 5
D. y > 5
E. 5 < y < 7

(Answer is apparently A…)






If a does not equal 0 and 5/x = (5+a)/(x+a) -without parentheses-, what is the value of x?

A. -5
B. -1
C. 1
D. 2
E. 5



If x^2 = x + 6, which of the following must be true?


A. x = 6
B. x < 3
C. x > 0
D. x^2 < x
E. x^2 > x

THANKS guys! If you can only answer one, please do. Please explain it, and also if you can explain the fastest way to solve it.