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Moving on to Question 3, If the third digit
of an acceptable product code is not 0, which

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one of the following must be true?

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Again, we have two possibilities here. We're saying that the third digit is not 0. So drawing

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out two possibilities.

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In Scenario 1 our options for the third spot are 0 and 3. If it's not 0 it's going to be

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3. Since the fifth digit must be greater than the third digit, or the third digit must be

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less than the value of the fifth digit, we
know that 4 must be fifth. We know 1 and 2

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would be first and second, which puts 0 in
four.

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What about for option 2? In option 2 our options for the third spot are 0 and 1. The stem from

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Question 3 is telling us it's not 0 so it
must 1. We know 2 and 4 now are going to be

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first and second. We know that the third digit is less than the value of the fifth digit.

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The only 2 digits remaining are 0 and 3, which means 3 has to go fifth and 0 comes fourth.

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Again, we're looking for what must be true. So Let's take a look:

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(A), the second digit of the product code
is 2. That's definitely possible in our

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first scenario, but it doesn't have to be
true because in scenario 2 the second digit

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is 4. So (A) is not necessarily true and (A)
is out.

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(B), the third digit of the product code
is 3. In scenario 1 that's true, but in

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scenario 2 it's 1, so (B) doesn't have to
true and (B) is out.

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(C), the fourth digit of the product code
is 0. You notice, in both of our scenarios

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here, 0 is the fourth digit. (C) must be true
and (C) would be the correct answer.