The ratio of north american butterflies to south american butterflies at a butterfly park is 9: 5. the ratio of south american to european butterflies is 5: 3. there are 135 north american butterflies at a butterfly park.

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how many south american butterflies are there?

there are south american butterflies.

You paid 28.00 for 8 gallons of gasoline. how much would you pay for 15 gallons of gasoline?

Amachine that produces a special type of transistor (a component of computers) has a 2% defective rate. the production is considered a random process where each transistor is independent of the others. (a) what is the probability that the 10th transistor produced is the first with a defect? (b) what is the probability that the machine produces no defective transistors in a batch of 100? (c) on average, how many transistors would you expect to be produced before the first with a defect? what is the standard deviation? (d) another machine that also produces transistors has a 5% defective rate where each transistor is produced independent of the others. on average how many transistors would you expect to be produced with this machine before the first with a defect? what is the standard deviation? (e) based on your answers to parts (c) and (d), how does increasing the probability of an event a↵ect the mean and standard deviation of the wait time until success?

Aconcession manager at yankee stadium wants to know how temperature affects beer sales. she took a sample of 10 games and recorded the number of beers sold and the temperature in the middle of the game. temperature 80 68 78 79 87 74 86 92 77 84 number of beers 20533 1439 13829 21286 30985 17187 30240 87596 9610 28742 a. draw a scatter plot of the data. b. the manager estimates the regression equation to be: numberofbeers = −100, 678 + 1, 513 ∗ temperature draw this on your scatter plot. c. for one of the estimated points, indicate the residual with ei . d. for that same point, indicate what part of the variation is explained by the model with ˆyi − y¯.