In a quiz, you receive 7 points for a correct answer and –4 points for an incorrect answer.You receive 0 points if you do not answer the question.There are 20 questions in total.Is it possible to get a score of –11 in this quiz?

Respuesta :

Answer:

Yes it is possible

Step-by-step explanation:

Given

[tex]n = 20[/tex]

[tex]x= 7[/tex] --- correct

[tex]y = -4[/tex] --- wrong

[tex]z = 0[/tex] --- empty answer

Required

Is a total of -11 possible?

To do this, we apply trial by error method.

After so many approaches, I found the following solution

[tex]x \to 3[/tex] -- Got 3 correctly

[tex]y \to 8[/tex] --- Failed 8

[tex]z \to 9[/tex] ---- Didn't answer 9

The above will give a score of -11.

We have:

[tex]3x+8y+9z[/tex]

[tex]3x+8y+9z = 3 * 7 + 8 * -4 + 9 * 0[/tex]

[tex]3x+8y+9z = 21-32 + 0[/tex]

[tex]3x+8y+9z = -11[/tex]

Hence, a score of -11 is possible