Hi, the following is a list of binomial cumulative distribution of the probability that out of 25 investors, the number of investors that would have exchange-traded funds in their portfolios.

We were asked for the probability that at least 14 investorsdo nothave exchange-traded funds in their portfolios from this table.

Binomial

n 25

p 0.4800

xi P(X<=xi)

0 0.0000

1 0.0000

2 0.0000

3 0.0002

4 0.0009

5 0.0037

6 0.0124

7 0.0342

8 0.0795

9 0.1585

10 0.2751

11 0.4220

12 0.5801

13 0.7260

14 0.8415

15 0.9197

16 0.9648

17 0.9868

18 0.9959

19 0.9989

20 0.9998

21 1.0000

22 1.0000

23 1.0000

24 1.0000

25 1.0000

Here is what I did: since they ask for at least 14 do not, it means 11 or less do. So the answer is .422---the cumulative of 11 and less that do.

But when I used the Binomial Cumulative Distribution function on my calculator Binomcdf (25, 0.52, 14), I get 0.725.

Where did I do wrong?

Thanks.