Question

In an exam every question correctly answered fetches 2 marks. Every question wrongly answered loses 1 marks. unanswered question have no marks associated with them. ram and shyam wrote this exam. ram attempted a certain number of questions and 30 % of them went wrong. shayam attempted a certain number of questions anf 40% of them went wrong. ram got 40 marks more than the pass mark. shyam got 25 marks more than the pass mark. the two of them together attempted a total of 100 questions. What is the pass mark ?

Answer 1

Answer:

The pass mark is 15.

Step-by-step explanation:

If the pass mark is "p" , then if Ram attempted "x" questions, then Shyam attempted (100 - x).

So,

2(0.7x) - 1(0.3x) = p + 40

2[0.6(100 - x)] - 1[0.4(100 - x)] = p + 25

Simplify both equations

1.4x - 0.3x = p + 40

120 - 1.2x - 40 + 0.4x = p + 25

p + 40 = 1.1x ....... (1)

p + 25 - 80 = - 0.8x ===> p - 55 = - 0.8x ........ (2)

Subtract (2) from (1), we get

95 = 1.9x ===> x = 50

p = 1.1 × 50 - 40

p = 15