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What two criteria are needed for triangles to be similar

An optical inspection system is used to distinguish among different part types. the probability of a correct classification of any part is 0.92. suppose that three parts are inspected and that the classifications are independent. let the random variable x denote the number of parts that are correctly classified. determine the probability mass function of x. round your answers to four decimal places (e.g. 98.7654). x f(x) 0 1 2 3

65% of students in your school participate in at least one after school activity. if there are 980 students in you school, how many do not participate in an after school activity?