To calculate the accumulated amount at the end of 6 years, we can use the future value of an ordinary annuity formula, taking into account the annual payments of Rs. 50,000 and the 6% interest compounded monthly.

The formula to calculate the future value of an ordinary annuity is:

FV = P * [(1 + r/n)^(n*t) - 1] / (r/n)

Where:
FV = Future value (accumulated amount)
P = Annual payment amount
r = Interest rate (in decimal form)
n = Number of compounding periods per year
t = Number of years

In this case:
P = Rs. 50,000
r = 6% = 0.06 (6% expressed as a decimal)
n = 12 (compounded monthly)
t = 6 years

Plugging these values into the formula, we have:

FV = 50000 * [(1 + 0.06/12)^(12*6) - 1] / (0.06/12)

Calculating this expression, we find that Smith will accumulate approximately Rs. 350,694.77 at the end of 6 years.