Problem Solving

Hi,

I thought the answer was D) by 50 - 2inc = 38 inc=6 therefore 50-6=44 but turned out the answer is E)...can anyone help?

An instructor scored a student’s test of 50 questions by subtracting 2 times the number of incorrect answers from the number of correct answers. If the student answered all of the questions and received a score of 38, how many questions did that student answer correctly?
(A) 19
(B) 38
(C) 41
(D) 44
(E) 46

Let c and i be the number of correct and incorrect questions resp.

We have 2 equations --

c - 2i = 38
c + i = 50

Solving for c, we get 46. Hence E

dunkin77 wrote:Hi,
I thought the answer was D) by 50 - 2inc = 38 inc=6 therefore 50-6=44 but turned out the answer is E)...can anyone help?

The problem lies in the underlined part,
The total marks = Number of Correct answers - 2* Incorrect answers
(no of correct answers is not 50 it is 50-inc)

now,

50-inc-2*inc=38
=> inc =4

that leaves 46 as the answer

oh! I seee.... Thank you!

Let total number of incorrect answers be x. Thus the teacher substracted 2x from the number of correct answers (number of correct answers would obviously be equal to 50 - x)

50 - x - 2x = 38

12 = 3x

x = 4. Hence correct answers = 50-4 = 46