1. Find the 15th term of the arithmetic senquence 26, 13, 0, -13, ... 2. Find the first term of the arithmetic sequence if the 8th term is 67.

3. Find the 23rd term of the arithmetic sequence 5, 11, 17,

4. What is the common difference of the arithmetic sequence whose first term is 10 7th term is 28?

5. Find the term of the sequence whose 200th term is 893 and common difference is 7,

To find the

n

t

h

term, we use the formula

x

n

=

a

+

d

(

n

−

1

)

, where

n

is the term you are looking for,

a

is the

1

s

t

term and

d

is the difference between terms (it does not vary)

From the arithmetic sequence

−

3

,

4

,

11

,

18

...

, we can see that

a

=

−

3

and

d

=

7

You can find

d

by subtracting a number by its precedent

⇒

d

=

4

−

(

−

3

)

=

7

or

d

=

11

−

4

=

7

and so on! It's always going to be the same value.

So,

x

15

=

−

3

+

7

(

15

−

1

)

=

−

3

+

7

(

14

)

=

−

3

+

98

=

95

Another way to do this since it's "only" the

15

t

h

term is by hands or calculator. They already gave you the four terms, which will help you find the difference "

d

". Use only the first term "

−

3

" and add 7 until you reach the

15

t

h

term.

⇒

−

3

+

7

+

7

+

7

+

7

+

7

+

7

+

7

+

7

+

7

+

7

+

7

+

7

+

7

+

7

=

95

Step-by-step explanation:

fourth month

step-by-step explanation:

it is the one with the most keychains.

if you need just tell me and i will come to the rescue.

step-by-step explanation: