__Questions 1:__

How much water should be added to 20 ounces of a 20% acid solution to reduce it to a 10% solution?

__Questions 2:__

Solve for C the following equation: B = 2 B D + 2 C E + 2 C L

__Questions 3:__

Thomas can paint the house in 6 days, while it takes Joe 12 days to paint the same house. How long would it take Thomas and Joe, working together, to paint the house?

__Questions 4:__

Solve the following system of equations

3x - 4y = 25

-2x + y = -10

__Questions 5:__

An airliner can make a 3,000 mile trip with tailwind (wind in the same direction as the airliner) in 4 hours and make the return trip against the wind (with the same speed) in 4 hours 48 minutes (4.8 hours). Find the ground speed of the airliner.

__Questions 6:__

Write as a single interval if possible: (-9 , 2) U (1 , 30)

__Questions 7:__

Solve the equation: |5x - 2| - 2 = 6

__Questions 8:__

Solve the inequality: |4x + 6| < 30

__Questions 9:__

Solve the inequality: |4x + 5| - 5 > 6

__Questions 10:__

Solve the inequality: SQRT (3x - 2)^{2} < 5

__Questions 11:__

Solve the equation: |-2x + 5| = 2x - 5

__Questions 12:__

Solve the equation: |4x - 2| = 8x - 12

__Questions 13:__

Evaluate and write in standard form: (4 - 2i)(-3 + 3i), where i^{2} = -1.

__Questions 14:__

Evaluate and write in standard form: (2 - 3i) / (2 - 2i), where i^{2} = -1.

__Questions 15:__

Evaluate and write in standard form: (-3 + 2i)^{2} - 3(3 - i)(-2 + 2i), where i^{2} = -1.

__Questions 16:__

Solve the equation: -(x - 2)^{2} - 2 = 7

__Questions 17:__

Solve the equation: (-x + 3)^{2} - 12 = 8

__Questions 18:__

Solve the equation: 3 + 30/x^{2} = -21/x

__Questions 19:__

Solve the equation: -x / (x^{2} + 2x - 3) + 5 / (x + 3) = 1

__Questions 20:__

The sum of a number and its reciprocal is 82 / 9. Find the number.

**ANSWERS TO ABOVE QUESTIONS**

1) 20 ounces

2) C = B(1 - 2D) / (2E + 2L)

3) 4 days

4) (3 , -4)

5) 687.5 miles/hour

6) (-9 , 30)

7) x = 2 , x = - 6 / 5

8) -9 < x < 6

9) (- infinity , -4) U (3/2 , + infinity)

10) (-1 , 7/3)

11) [5/2 , + infinity)

12) x = 5/2

13) -6 + 18 i

14) 5/4 - i / 4

15) 17 - 36 i

16) x = 2 + 3 i , x = 2 - 3 i

17) x = 3 + 2 SQRT(5) , x = 3 - 2 SQRT(5)

18) x = -2 , x = -5

19) x = 1 + i , x = 1 - i

20) Two possible solutions: x = 9 and x = 1 / 9

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