Find P20

here is the data set

0.1

0.2

0.2

0.3

0.4

0.4

0.4

0.5

0.5

0.6

0.6

0.6

0.6

0.7

0.8

0.8

1.2

1.3

1.7

1.7

1.8

1.9

2.1

2.1

2.2

2.2

2.7

2.8

3.3

3.4

3.7

4.8

5.8

6.4

7.5

7.6

9.1

9.4

10.5

11.2

11.2

12.2

12.7

13.4

13.9

14.3

14.4

15.4

15.7

27.4