To find the average price paid for the shares, we need to calculate the total amount spent on shares and divide it by the total number of shares bought.

The total amount spent on shares can be calculated by multiplying the number of shares bought each month by the price per share and summing them up.

In this case, the investor bought shares worth Rs. 1,200 each month for 5 months. So, the total amount spent on shares is:

Total amount spent = (Rs. 1,200/month) x 5 months = Rs. 6,000

Now, we need to calculate the total number of shares bought. The number of shares bought each month is the total amount spent divided by the price per share.

Number of shares bought in the first month = Rs. 1,200 / Rs. 10 = 120 shares Number of shares bought in the second month = Rs. 1,200 / Rs. 12 = 100 shares Number of shares bought in the third month = Rs. 1,200 / Rs. 15 = 80 shares Number of shares bought in the fourth month = Rs. 1,200 / Rs. 20 = 60 shares Number of shares bought in the fifth month = Rs. 1,200 / Rs. 24 = 50 shares

Total number of shares bought = 120 + 100 + 80 + 60 + 50 = 410 shares

Finally, we can calculate the average price paid for the shares by dividing the total amount spent by the total number of shares bought:

Average price paid = Total amount spent / Total number of shares bought Average price paid = Rs. 6,000 / 410 shares Average price paid ≈ Rs. 14.63 per share

Therefore, after 5 months, the average price paid for the shares by the investor is approximately Rs. 14.63 per share.