Question

if a student scored 25% marks then he is faild
by 210 marks.but he scores 55% then he is passed with 240 mark.find the passing percentage​

Answer 1

Solutions :-

Given :
A student scored 25% marks then he is failed by 210 marks.
But he scores 55% then he is passed with 240 marks.

Let the maximum marks be x

According to the question,

25% of x + 210 = 55% of x - 240
=> 0.25x + 210 = 0.55x - 240
=> 0.25x - 0.55x = - 240 - 210
=> - 0.30x = - 450
=> x = - 450/- 0.30 = 1500

Find the passing percentage :-

Pass marks = 25% of 1500 + 210
= 375 + 210
= 585

Pass percentage = (pass marks × 100)/Maximum marks %
= (585 × 100) / 1500 %
= 58500/1500 %
= 39 %

Hence,
Passing percentage = 39%

Answer 2

Solutions :-

Let the total marks be x
And pass marks be y

According to the question,

25% of x + 210 = y
=> 0.25x + 210 = y ______(1)
55% of x - 240 = y
=> 0.55x - 240 = y _____(2)


Subtract the equation (2) from (1),

(0.25x + 210) - (0.55x - 240) = y - y
=> 0.25x + 210 - 0.55x + 240 = 0
=> - 0.30x = - 450
=> x = - 450/ - 0.30 = 1500


Now,
Putting the value of x in the equation (1)

0.25 × 1500 + 210 = y
=> 375 + 210 = y = 585


Passing percentage = (585 × 100)/1500 %
= 58500/1500 %
= 39 %


Answer : Passing percentage = 39%