Banking Quantitative Aptitude Sample Paper Quantitative Aptitude Sample Paper-42

Two numbers are in the ratio 1: 2. When 4 is added to each, the ratio becomes 2: 3. Then, the numbers are [SSC (CGL) 2014]

A) 9 and 12

B) 6 and 8

C) 4 and 8

D) 6 and 9

Correct Answer: C

Solution :

Let the two numbers be x and y, respectively.

\[\therefore \] \[\frac{x}{y}=\frac{1}{2}\] [given]

\[\Rightarrow \] \[y=2x\] ... (i)

Now, when 4 is added to each number the ratio becomes 2: 3.

Then, \[\frac{x+4}{y+4}=\frac{2}{3}\]

\[\Rightarrow \]\[3x+12=2y+8\]

\[\Rightarrow \]\[3x+12=2\,\,(2x)+8\] [from Eq. (i)]

\[\Rightarrow \]\[3x+12=4x+8\]

\[\Rightarrow \]\[x=4\]

Now, from Eq. (i)

\[y=2x\]

\[\Rightarrow \] \[y=2\times 4=8\]

So, the numbers are 4 and 8.