Question 1114164
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<pre>
Let x = all the population of the class.


{{{(3/4)*x}}} = 0.75x  got a C.


{{{(1/5)*x}}} = 0.2x  got an A.


The difference  is  0.75x - 0.2x = 0.55x,  or 22.


The equation is  0.55x = 22.


The answer is  {{{22/0.55}}} = 40.
</pre>

Solved.