Mohit and Sudesh bought pens and notebooks from the same shop. Mohit bought 3 pens and 6 notebooks by paying an amount of `180. Sudesh bought 5 pens and 2 notebooks by paying an amount of `116. How much did Mohit spend on buying notebooks?

To find out how much Mohit spent on buying notebooks, we can set up a system of linear equations based on the information provided in the question.

Let the cost of one pen be $x$ rupees and the cost of one notebook be $y$ rupees.

From the problem statement:
1. Mohit bought 3 pens and 6 notebooks for ₹180:
$3x+6y=180$ (Equation 1)
2. Sudesh bought 5 pens and 2 notebooks for ₹116:
$5x+2y=116$ (Equation 2)

First, we can simplify Equation 1 by dividing the entire equation by 3:
$x+2y=60$
From this, we can express $x$ in terms of $y$:
$x=60-2y$ (Equation 3)

Now, substitute the value of $x$ from Equation 3 into Equation 2:
$5(60-2y)+2y=116$
$300-10y+2y=116$
$300-8y=116$
$8y=300-116$
$8y=184$
$y=\frac{184}{8}$
$y=23$

So, the cost of one notebook is ₹23.

We are asked to find the total amount Mohit spent on notebooks. Mohit bought 6 notebooks.
Amount spent by Mohit on notebooks = $6\times y$
Amount spent by Mohit on notebooks = $6\times 23=138$

Thus, Mohit spent ₹138 on buying notebooks.