Ella bought some key chains and spent a total of $15. Each key chain cost the same whole-dollar amount. She bought between 4 and 9 key chains. How many key chains did Ella buy? Ella bought key chains

5

Step-by-step explanation:

Total amount spent = $15

Number of chain purchased is between 4 and 9

Cost per chain is a the same (whole dollar)

Number of Chain purchased = (total cost / cost per chain)

Since the total cost = $15

The only whole number value which can divide $15 without a remainder and give a value between between 4 and 9 is 3.

Therefore, cost per chain = $3

Hence, number of chain purchased = $15 / $3

= 5

what are the things "represented below"?

step-by-step explanation:

nobody can if you dont give the choices

, and

for

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