Answers

2016-07-18T23:48:16+08:00
The 18 girls constitutes for the remaining 2/5 of the class. Solving it algebraically, 

Let x be the total number of students
(2/5)x = 18
2x      = 90
x        = 45

To check, just get the 2/5 of 45 and you'll get 18. The answer is correct 
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