# Question: The daily exchange rate of one dollar in euros during

The daily exchange rate of one dollar in euros during the first three months of 2007 can be inferred to have the following distribution.

X P(x)

0.73 ... 0.05

0.74 ... 0.10

0.75 ... 0.25

0.76 ... 0.40

0.77 ... 0.15

0.78 ... 0.05

a. Show that P(x) is a probability distribution.

b. What is the probability that the exchange rate on a given day during this period will be at least 0.75?

c. What is the probability that the exchange rate on a given day during this period will be less than 0.77?

d. If daily exchange rates are independent of one another, what is the probability that for two days in a row the exchange rate will be above 0.75?

X P(x)

0.73 ... 0.05

0.74 ... 0.10

0.75 ... 0.25

0.76 ... 0.40

0.77 ... 0.15

0.78 ... 0.05

a. Show that P(x) is a probability distribution.

b. What is the probability that the exchange rate on a given day during this period will be at least 0.75?

c. What is the probability that the exchange rate on a given day during this period will be less than 0.77?

d. If daily exchange rates are independent of one another, what is the probability that for two days in a row the exchange rate will be above 0.75?

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