Please help
(Both images are supposed to be together)

The second club has a better deal for 6 months.

Step-by-step explanation:

First you figure out the cost for the first club by multiplying 30 by 6 = 180 dollars for 6 months.

Next you can calculate how much it would cost for the second club.  If it is 145 dollars for 5 months, then you divide 145 by 5 and get 29 which is your conversion factor.  Then multiply your conversion factor by the number of months, which is 6 in this case, to get your month cost.  

Just by seeing 6x29 you see that it is less than 6x30 by 6 so you have your answer.  The second club is better to join for six months

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step-by-step explanation:

we can analyze the pattern at which the terms increase. let us denote , , , so that we can call

note the following:

the pattern: to get the next term value, we just add the next term number (e.g. 1st, 2nd, to the previous term value (term values are the given numbers in the question, 1, 3, 6, 10, 15,

from , to get to , we add

from , to get to , we add

etc.

we need to form a recursive formula, a formula that has the next term as a function of the previous term. so a possible recursive formula can be

, and for

answer: the actual answer is a. good bank will have the least amount in fees per year.