# 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 = n

I 0

II 16

III-20

an = n

^{2}- 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?

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 Then what is [x]

**.**[x]**.**[x] ?A. ∛x B.√3x C. x √x D. x

^{3}E. ∛x

^{2}

**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. a

^{2}/2 B. a

^{2}C. 2a

^{2}D. 3a

^{2}E. 4a

^{2}

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