Question

hich of the following does not represent the set of integers from 1 to 12?

{1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12}

{integers from 1 to 12}

{1, 2, 3, … 10, 11, 12}

{1, 2, 3, 4, …}

Answer 1

Look at each one carefully. What do you think of the first one? Are those the integers from 1 to 12?

Answer 2

yea cause its from 1-12

Answer 3

Now what about the second one?

Answer 4

Good.
Now look at the second choice. What do you think of it?

Answer 5

just says integerrs from 1-12 doesnt list them just says it

Answer 6

But it still means the same thing right?

Answer 7

Yes, but that set only contains what the descriptioon states. So it is good.

Answer 8

Now look at the 3rd choice. What does that set contain?

Answer 9

stops at 3 but is missing 456789

Answer 10

But notice the three dots. That means continue the same way until 10, etc. So it also means the integers from 1 to 12.

Answer 11

Now look at the last choice. It also has the three dots, but nothing after the three dots. What does that mean?

Answer 12

stops at 4 but after the ... doesnt go on from there

Answer 13

No, basically the ... means it continues until stopped. So before it was stopped by the number 10 right? But now there is no stopper number, so it means all the numbers after 4, forever.

So thats the wrong choice.

Answer 14

Notice again. What do the three dots after the 4 mean?

Answer 15

the secons one then

Answer 16

No. The last one is all integers, starting with 1 and going on forever. That is certainly not the integers from 1 to 12, so the 4th choice is the answer to the question.

Answer 17

ohhhhhh ok cause it wont stop at 12 got i

Answer 18

Exactly.