Carcass wrote:

If y = 3x and z = 2y, then in terms of x, x + y + z =

(A) 10x

(B) 9x

(C) 8x

(D) 6x

(E) 5x

Another approach is to TEST a certain value of x.

For example, let's see what happens if x =

7If y = 3x, then y = 3(

7) = 21

Next, if z = 2y, then z = 2(21) = 42

So, x + y + z =

7 + 21 + 42 =

70In other words, when x =

7, x + y + z evaluates to be

70Now we'll plug x =

7 into the answer choices to see which one yields an output of

70(A) 10(

7) =

70 PERFECT!

(B) 9(

7) =

63 Doesn't match - ELIMINATE

(C) 8(

7) =

56 Doesn't match - ELIMINATE

(D) 6(

7) =

42 Doesn't match - ELIMINATE

(E) 5(

7) =

35 Doesn't match - ELIMINATE

Answer: A

_________________

Brent Hanneson – Creator of greenlighttestprep.com

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