Ivan Loves Classical Music,and His Favorite Composer Wrote Nine Symphonies

Ivan loves classical music,and his favorite composer wrote nine symphonies.Ivan just happens to the 9 symphonies in exactly the order in which they were written.The table below shows the values that Ivan places on having these symphonies which he does not currently yet own:
Rank Total Personal Value
1_______________19
2_______________36
3_______________51
4_______________64
5_______________75
6_______________84
7_______________91
8_______________96
9_______________99
You can interpret the above to mean,for example,that Ivan values her favorite Symphony at $19,and that the total value of the first Symphony plus Symphony # 2 (his second favorite)is $36,etc.If the symphonies were sold individually on CDs - one symphony per disc - and the price per CD was $10.00,how many CDs would he buy?
[The above question was inspired by a question by Victor Tabush]