what is the total no. of candidates at an examination if 31% fail and the number of those who passed exceed the number of those who failed by 247.

Solution:

Let us assume that the total number of candidates in the examination = x

Then the number of candidates failed = 31% of x = 31/100 of x = 31x/100.

Therefor the total number of candidates passed = (31x/100 + 247) = (31x + 24700 / 100).

So the equation we get is :

31x/100 +(31x + 24700 / 100) = x

(31x +31x + 24700) / 100 = x

62x + 24700 = 100x

62x - 100x = -24700

- 38x = - 24700

x = - 24700/-38 = 650

Ans:Total numbers of candidates in the examination = 650 Nos.