table of contents adobe inc . notes to consolidated financial statements ( continued ) goodwill , purchased intangibles and other long-lived assets goodwill is assigned to one or more reporting segments on the date of acquisition . we review our goodwill for impairment annually during our second quarter of each fiscal year and between annual tests if an event occurs or circumstances change that would more likely than not reduce the fair value of any one of our reporting units below its respective carrying amount . in performing our goodwill impairment test , we first perform a qualitative assessment , which requires that we consider events or circumstances including macroeconomic conditions , industry and market considerations , cost factors , overall financial performance , changes in management or key personnel , changes in strategy , changes in customers , changes in the composition or carrying amount of a reporting segment 2019s net assets and changes in our stock price . if , after assessing the totality of events or circumstances , we determine that it is more likely than not that the fair values of our reporting segments are greater than the carrying amounts , then the quantitative goodwill impairment test is not performed . if the qualitative assessment indicates that the quantitative analysis should be performed , we then evaluate goodwill for impairment by comparing the fair value of each of our reporting segments to its carrying value , including the associated goodwill . to determine the fair values , we use the equal weighting of the market approach based on comparable publicly traded companies in similar lines of businesses and the income approach based on estimated discounted future cash flows . our cash flow assumptions consider historical and forecasted revenue , operating costs and other relevant factors . we completed our annual goodwill impairment test in the second quarter of fiscal 2018 . we determined , after performing a qualitative review of each reporting segment , that it is more likely than not that the fair value of each of our reporting segments substantially exceeds the respective carrying amounts . accordingly , there was no indication of impairment and the quantitative goodwill impairment test was not performed . we did not identify any events or changes in circumstances since the performance of our annual goodwill impairment test that would require us to perform another goodwill impairment test during the fiscal year . we amortize intangible assets with finite lives over their estimated useful lives and review them for impairment whenever an impairment indicator exists . we continually monitor events and changes in circumstances that could indicate carrying amounts of our long-lived assets , including our intangible assets may not be recoverable . when such events or changes in circumstances occur , we assess recoverability by determining whether the carrying value of such assets will be recovered through the undiscounted expected future cash flows . if the future undiscounted cash flows are less than the carrying amount of these assets , we recognize an impairment loss based on any excess of the carrying amount over the fair value of the assets . we did not recognize any intangible asset impairment charges in fiscal 2018 , 2017 or 2016 . during fiscal 2018 , our intangible assets were amortized over their estimated useful lives ranging from 1 to 14 years . amortization is based on the pattern in which the economic benefits of the intangible asset will be consumed or on a straight-line basis when the consumption pattern is not apparent . the weighted average useful lives of our intangible assets were as follows : weighted average useful life ( years ) .

weighted averageuseful life ( years ): purchased technology: 6
customer contracts and relationships: 9
trademarks: 9
acquired rights to use technology: 10
backlog: 2
other intangibles: 4

income taxes we use the asset and liability method of accounting for income taxes . under this method , income tax expense is recognized for the amount of taxes payable or refundable for the current year . in addition , deferred tax assets and liabilities are recognized for expected future tax consequences of temporary differences between the financial reporting and tax bases of assets and liabilities , and for operating losses and tax credit carryforwards . we record a valuation allowance to reduce deferred tax assets to an amount for which realization is more likely than not. .

Questions:
what was the weighted average useful life for purchased technology, in years?
and what was it for customer contracts and relationships, also in years?
what was, then, the total of years in weighted average useful life for both of those intangible assets?
and what is the average between them?

Answers:
6
9
15.0
7.5