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A student takes a multiple choice test consisting of 5 questions where there are 4 choices per question. Also, each question is worth 20 points. Suppose the student guesses on each question. Let X be the number of questions the student gets correct. The probability distribution for X is given below. Find the mean score a student that guesses will receive on the test. Do not give units. Hint: X represents the number of questions the students get correct. This is not the same as the score they get on the test.

x | 0 | 1 | 2 | 3 | 4 | 5 |

P(X=x) | 0.2373 | 0.3955 | 0.2637 | 0.0879 | 0.0146 | .0010 |

The formula used here is the formula for calculating the expected value (mean) of a discrete random variable.