Liberty Bank has just made a large infrastructure loan of $300mn. Its balance sheet prior to making the loan is as follows:

Assets	$ millions	Liabilities	$ millions
Cash	100	Deposits	610
Loan portfolio	600	Equity	90
Total assets	700	Total liabilities and equity	700

Duration of assets in the table above = 6 years

Duration of liabilities in the table above = 3 years

Assuming the new infrastructure loan has a duration of 7.5years, calculate the new duration of the banks assets after giving out this loan. Give your answer to 1 decimal place. Do not include any units.