Question

please someone answer this question correctly...it's correct answer is option D...But i need step by step explanation​

Answer 1

30%/40% = 30/ 40

= 6/8

= 3/2

= 40 + 25 + 100

= 165 + 80

= 245

= 245 × 3/2%

Answer 2

Answer:

D

Step-by-step explanation:

Wrong = -1

Correct = 2

Let attempted questions be X by Ram

Let attempted questions be Y by Shyam

Let Passing marks be P

X + Y =100 ---------(1)

Ram:     (0.7X)(2) + (0.3X)(-1)= P+ 40

 => 1.4X – 0.3X = P + 40

 => 1.1X = P +40   ----------------(2)

Shyam: (0.6Y)(2) + (0.4Y)(-1) = P + 25

 1.2Y – 0.4Y = P + 25

 0.8Y = P + 25   --------------(3)

From 2 & 3,

1.1 X – 0.8Y = 15 --------------(4)

  (4)x10

11X – 8Y = 150  - ------------(4)

8x(1) + (4) =>

19X = 150 + 800

19X = 950

X= 50

Y = 50

Putting X in (2)

P = 15

Max Marks = 80x2= 160

 Marks secured = 55      

Marks % = 55/160 = 0.34375= 34.375%