Question

6. In a Mathematics test, there are 60 questions. There is 2 marks for every correct answer, and 1/3 marks
deducted for each unattempted question or wrong solution. If Zaheer got 50 marks, how many questions
did he answer correctly?
mark is​

Answer 1

ɢɪᴠᴇɴ :-

In a Mathematics test, there are 60 questions. There is 2 marks for every correct answer, and 1/3 marks deducted for each unattempted question or wrong solution. If Zaheer got 50 marks.

ᴛᴏ ғɪɴᴅ :-

Number of :-

• Correct answers
• Wrong answers

sᴏʟᴜᴛɪᴏɴ :-

Let the number of correct answer be x and wrong answers be y

then,

✞ According to 1st condition :-

➭ Total no of answers = 60

➭ Correct ans + Wrong ans = 60

➭ (x + y) = 60. ---(1)

✞ According to 2nd condition :-

$\implies \tt \: 2x - \frac{y}{3} = 50 \\ \\ \\ \implies \tt \: \frac{2x \times 3}{1 \times 3} - \frac{y}{3} = 50 \\ \\ \\ \implies \tt \: \frac{6x - y}{3} = 50 \\ \\ \\ \implies \tt \: 6x - y = 50 \times 3 \\ \\ \\ \implies \tt \: 6x - y = 150$

We get,

➭ 6x - y = 150. --(2)

On adding (1) and (2) , we get

➭ (x + y) + (6x - y) = 60 + 150

➭ x + 6x = 210

➭ 7x = 210

➭ x = 210/7

➭ x = 30

Put x = 30 in (1) , we get,

➭ x + y = 60. --(1)

➭ 30 + y = 60

➭ y = 60 - 30

➭ y = 30

Hence,

• Number of correct answer = 30
• Number of Wrong answers = 30

Answer 2

Answer:

30

Step-by-step explanation:

let the no. of correct answers be x

and no. of wrong answers be y

according to the condition

x+y=60

x=60-y ----- eqn 1

2x -1/3y=50

putting the value of xx in eqn 1

2(60-y)-1y/3=50

120-2y-1y/3=50

-2y-1y/3=-70

-6y-y/3=-70

-7y=-210

y=30

putting the value of y in eqn 1

x=60-30

x=30

the number of questions he answered correctly is 30