# Math Puzzle 16

This math puzzle 16 is based on sequence and series.

1) How many terms are there in the sequence 729,243,81,27......1/3?
A. 5     B. 6     C. 7     D. 8     E. 9

2) If two numbers x and y are inserted between 50 and -49 such that 50, x, y, -49 form an arithmetic sequence, what is x + y?
A. -3     B. -2    C. -1     D. 0     E. 1

3) Which of the following numbers belong to the sequence
an = n2 - 15n + 30?
I 0
II 16
III-20

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

4) In a group of 30 students, 17 play only hockey and 10 play only baseball. If each student has to play at least one game, how many students play both the games?
A. 3     B. 5     C. 7     D. 9     E. 10

5) Set A = {3,5,9,22,23,40,45} and set B = {1,2,3,5,8,23,45,51}. What is the mean of elements of intersection between A & B?
A. 10.33    B. 18.75    C. 19     D. 24.33     E. not enough information

6) Let be defined for all real value of x be the equation = 3x -1.
If 3 - = x, then what is x?

A. 1     B. 2     C. -1     D. -2     E. 0

7) Refer the following definition: For all positive integers x,
[x] =√x Then what is [x]. [x]. [x] ?

A. ∛x B.√3x C. x √x D. x3 E. ∛x2

8) Let the operation ∆ be defined for all positive integers a and b by the equation a ∆ b = a + ab - b. For what value of a is a ∆ 3=21?
A. 3     B. 4     C. 6     D. 9     E. 12

9) Which of the following statements is equivalent to |2x-1| < 7 for all x?
A. x < 4     B. -3< x< 4     C. x > -3     D. x > 4     E. x < -4

10)What is the area of the figure generated by the intersection of lines |x| = a and |y| = a?
A. a2 /2    B. a2     C. 2a2     D. 3a2     E. 4a2

Math Puzzle 16

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