### All GRE Math Resources

## Example Questions

### Example Question #9 : Sequences

The sequence is defined by:

What is ?

**Possible Answers:**

**Correct answer:**

Begin by interpreting the general definition:

This means that every number in the sequence is five greater than the element preceding it. For instance:

It is easiest to count upwards:

### Example Question #2 : Sequences

The sequence is defined by:

What is the value of ?

**Possible Answers:**

**Correct answer:**

For this problem, you definitely do not want to "count upwards" to the full value of the sequence. Therefore, the best approach is to consider the general pattern that arises from the general definition:

This means that for every element in the list, each one is greater than the one preceding it. For instance:

Now, notice that the first element is:

The second is:

The third could be represented as:

And so forth...

Now, notice that for the third element, there are only *two* instances of . We could rewrite our sequence:

This value will always "lag behind" by one. Therefore, for the st element, you will have:

### Example Question #1 : Nth Term Of An Arithmetic Sequence

The sequence is defined by:

What is the value of ?

**Possible Answers:**

**Correct answer:**

For this problem, you definitely do not want to "count upwards" to the full value of the sequence. Therefore, the best approach is to consider the general pattern that arises from the general definition:

This means that for every element in the list, each one is less than the one preceding it. For instance:

Now, notice that the first element is:

The second is:

The third could be represented as:

And so forth...

Now, notice that for the third element, there are only *two* instances of . We could rewrite our sequence:

This value will always "lag behind" by one. Therefore, for the th element, you will have: