<PRE><B>Question 1100904</B>
 the average marks obtained by boys in english is 39.
 If 4 the boys who actually obtained 5,12,15 and 19 marks had not been sent up, the average marks would have been 44.
 Find the number of boys.
:
let b = no. of boys
:
Find the total marks of those 4 boys
5+12+15+19 = 51
the equation
{{{(44(b-4) + 51)/b}}} = 39
44b - 176 + 51 = 39b
44b - 125 = 39b
44b = 39b = 125
5b = 125
b = 125/5
b = 25 boys

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