4. Mr. Llama takes out a loan in the amount of X. He can repay the loan by making 180 level end of month payments with the nominal rate of interest being 7.2% convertible monthly. Alternatively, he can pay the principal and interest in one lump sum at the end of 15 years. If he pays the loan back in one lump sum, he will pay 40,000 more in interest than if he repaid with 180 level monthly payments. Find X