# Exam

Exam

1.- The expression for the sentence "the double of a number minus seven units" is ...

 a) 2x - 7 b) 2·(x - 7) c) -2x - 7 d) None of them

2.- The value of the expression "3x - 2·(x- 4) - 17" if x = 4 is

 a) 5 b) 12 c) -5 d) None of them

3.       x + 3y - 5 + 3x - y + 11 - 2y =

 a) 4x + 6 b) 4x - 6y + 6 c) 4x - 6y - 6 d) None of them

4.- (-2x3y2z5)·(10xyz) =

 a) -8x4y3z6 b) -20x3y2z5 c) -20x4y3z6 d) None of them

5.- Decide if " 3·(x - 2) = 3x - 6" is an equation or an identity

 a) Identity b) Equation c) Both of them d) None of them

6.     x + 7 - 3·(x + 3) = 5x

 a) x = 0 b) x = 2/7 c) x = 1 d) x = -2/7

7.      2x - 7 - 3·(x + 1) = 5x - 2·(x + 5)

 a) x = 0 b) x = -2 c) x = -4 d) x = 5

8.

 a) x = 7 b) x = 0 c) x = -14 d) x = 14

9.- One kilo of apples costs twice as much as one kilo of oranges. If I paid 11 € for 3 kg of apples and 4 kg of oranges. How much does a kilo of each one cost?

 a) oranges 2,20 €/kg and apples 1,10 €/kg b) oranges 1,10 €/kg and apples 2,20 €/kg c) oranges 2 €/kg and apples 1 €/kg d) oranges 1 €/kg and apples 2 €/kg

10.- The sum of three consecutive numbers is 84. Calculate the numbers.

 a) 27, 28 and 29 b) 28, 29 and 30 c) 26, 27 and 28 d) 30, 31 and 32