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كيف احل ذي

A student takes a 8-question multiple choice quiz with 4 choices for each question. If the student guesses at random on each question, what is the probability that the student get zero score in this quiz?

0.1
0.12
0.35
0.07
p(all do)=p(3\4)^8
=0.1
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A group consisting of 4 numbers is to be formed from 10 even numbers and 8 odd numbers. Findthe probability that the group will consist of even number only.

0.119
0.049
0.069
0.039
نستخدم التوافيق combination
10C4\18C4
=0.069
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If the letters A,B,C,D,E, and F are to be used in a letter code consists of 7 digits, how many differentcodes are possible if the first letter must be A and repetitions are not permitted?

-4
0
5
7
_×_×_×_×_×_×_
6×5×4×3×2×1×0
=0