If the price of the TV screen is K500 and firm advertise the TV screen at K50 quarterly payments for eight months. What is the flate interest rate been charged on the loan?

To calculate the flat interest rate being charged on the loan, we first need to determine the total amount paid over the 8-month period.

Total amount paid = K50 * 8 = K400

Next, we need to determine the interest charged on the loan:

Interest charged = Total amount paid - Price of TV screen
Interest charged = K400 - K500 = K100

Finally, we can calculate the flat interest rate by dividing the interest charged by the original price of the TV screen:

Flat interest rate = (Interest charged / Price of TV screen) * 100
Flat interest rate = (K100 / K500) * 100 = 20%

Therefore, the flat interest rate being charged on the loan is 20%.