Help with the nth term?

Question

For each of the following sequences:

i) write down the next two terns,

ii) give an expression for the nth term.

a) 5,8,11,14,17,...

b) 5,9,13,17,21,...

c) 0.25, 1.25, 2.25, 3.25, 4.25

I don't understand the nth term can anyone help me and explain the answers and how you got them step by step or give me a website where i can get help for this kinda question i have a test coming up on it.

Basically heres what i don't understand about it take this question for example

a) 5, 8, 11, 14, 17 the answer i would probably get is 3n but thats not right and i don't understand how to get the right answer

Answer 1

it sounds like your taking an IQ test. if not you should take one thair are alot of questions like that in thair. try searching IQ test on yahoo.

PS i got an IQ score of 137 last time i took an IQ test.

Answer 2

If n is the term number, then k(n-1) is the difference between the first term and the nh term. Hence:

a. The given series is an arithmetic series with an interval of 3 and with 5 as the first term. The nth term therefore is;

N = 5 + 3(n-1)

Where;

N = the value of the term

n = the term number

Example: if we want to find the 101th term,

N = 5 + 3(101 - 1) = 305

b. The series is also an arithmetic series with interval of 4 with 5 as the first term. Thus;

N = 5 + 4(n-1)

c. The series is also an arithmetic series with interval of 1 with 0.25 as the first term. Thus;

N = 0.25 + (n - 1)

Answer 3

it's a basic formula so you could tell what the nth term will be.

Since term numbering starts from 1 to N (including only integral figures), we do it like that:

a)

An=a1+(n-1)*r where:

a1=the first figure in the chain in this case 5

r=a2-a1 since this is an arthmetic term, in this case it's 8-5=3

so:

An=5+(n-1)*3

A3=5+(3-1)*3=5+6=11, and indeed the 3rst figure in the A chain is 11!

Do it similar way with b and c :)

it's not IQ test, it's sheer mathematics...:

edit:

here you go:

http://en.wikipedia.org/wiki/Arithmetic_...