The number of students in three sections of a class in a school are in the ratio 5 : 7 : 8.If 20, 25 and 40 more students are admitted in the three sections, respectively, the new becomes 9 : 12 : 16. The total number of students after the new admission is:
Show answer & explanation
Correct answer: D
Explanation
The correct answer is option 4 i.e. 185.
Let original numbers be 5x, 7x, 8x
After admission:
5x + 20 : 7x + 25 : 8x + 40 = 9 : 12 : 16
Use first two parts:
(5x+20/9) = (7x + 25) ⇒ x = 5
Now total after admission:
= (25+20) + (35+25) + (40+40) = 185