A marketing expert for a pasta-making company believes that 40% of pasta lovers prefer lasagna. If 9 out of 20 pasta lovers choose lasagna over other pastas, what can be concluded about the expertís claim? Use a 0.05 level of significance.
(Textbook Ans : P-value = 0.4044 (with a one-tailed test); the claim is not refuted).
Using binomial distribution to get the P-Value, i have n=10,p=0.40, r=9 and so my answer = 2x 0.7553 (looking up the table) = 1.5106.
(while textbook ans is 0.4044)
so where have i gone wrong ?