Examveda
Examveda

The number of students in 3 classes is in the ratio 2 : 3 : 4. If 12 students are increased in each class this ratio changes to 8 : 11 : 14. The total number of students in the three classes in the beginning was

A. 162

B. 108

C. 96

D. 54

Answer: Option A

Solution(By Examveda Team)

Let the number of students in the classes be 2x, 3x and 4x respectively;
Total students = 2x + 3x + 4x = 9x
$$\eqalign{ & {\text{According}}\,{\text{to}}\,{\text{the}}\,{\text{question}}, \cr & \frac{{ {2x + 12} }}{{ {3x + 12} }} = \frac{8}{{11}} \cr & or,\,24x + 96 = 22x + 132 \cr & or,\,2x = 132 - 96 \cr & or,\,x = \frac{{36}}{2} = 18 \cr & {\text{Hence,}} \cr & {\text{Original}}\,{\text{number}}\,{\text{of}}\,{\text{students}}, \cr & 9x = 9 \times 18 \cr & \,\,\,\,\,\,\,\, = 162 \cr} $$

This Question Belongs to Arithmetic Ability >> Ratio

Join The Discussion

Comments ( 8 )

  1. Jiad Ali
    Jiad Ali :
    3 years ago

    Wow

  2. Harshavardhan P
    Harshavardhan P :
    4 years ago

    Easy guys take two ratio
    2 : 3
    +12 +12
    8 : 11
    Cross multi and sub
    8×3-11×2 = 11×12-8×12
    2=36
    1=18
    Total origina sum 9×18 =162

  3. Samiran Dey
    Samiran Dey :
    5 years ago

    where is 4+12??

  4. Apratim Ghosh
    Apratim Ghosh :
    5 years ago

    Why we not consider 14?

  5. Ghulam Akbar
    Ghulam Akbar :
    6 years ago

    ye kese hoa ...??
    24x+96 = 22x+132
    Or, 2x = 132-96
    Or, x = 36/2 = 18
    Hence, Original number of students,
    9x = 9*18 = 162.

  6. Jay Mangukiya
    Jay Mangukiya :
    7 years ago

    Any essy mathed.. Its very hard

  7. Kumar Chandan
    Kumar Chandan :
    8 years ago

    Cross-multiplication has been done.
    (2x+12)/(3x+12) = 8/11
    11*(2x+12) = 8 *(3x+12)
    24x+96 = 22x+132

  8. Saud
    Saud :
    8 years ago

    i didn't understand from where it comes 24x+96 = 22x+132

Related Questions on Ratio