Question

Margaret took a trip to Italy. She had to convert US dollars to euros to pay for her expenses there. At the time she was traveling, the conversion rate was represented by the function E(n)=0.72n, where n is the number of dollars and E(n) is the equivalent value in euros. Later, she traveled to Dubai and converted her remaining euros into the local currency, UAE dirhams. At that time, the conversion rate was represented by the function D(x)=5.10x, where x is the number of euros and D(x) is the equivalent value in dirhams. Which function can be used to convert n dollars directly to dirhams?

A) (D x E)(n) = 5.10(0.72n).
B) (D x E)(n) = (5.10x) x (0.72n).
C) (E x D)(n) = 0.72(5.10n).
D) (E x D)(n) = (0.72n) x (5.10x).

Answer 1

answer is A

Explanation:

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Answer 2

Answer: Hello!

So if Margaret has initial N dollars, and we know that the conversion for dollars to euros is E(n) = 0.72n, and from euros to dirhams is D(x) = 5.10x where x is euros.

Now, she first goes from dollars to euros, so she has:

E(N) = 0.72N euros, because she changes the N dollars for euros.

now she goes from euros to Dirhams, so now x = 0.72N

then D(0.72N) = 5.10*0.72*N

Then the change from N dollars to dirhams is:

(DxE)(N) = 5.10(0.72N)

then A is the correct answer.