Question

Natalie borrowed money from her parents to pay for a trip.

​Natalie will ​pay her parents in equal amounts every week until she pays back the ​entire amount she borrowed.

The table below shows the amount of ​money Natalie still owes her parents at the end of every two weeks for ​the first eight weeks.

Number of Weeks Natalie Has Paid, Amount Natalie Still Owes,
0 $180.
2 $162.
4 $144.
6 $126.
8 $108.

How much does Natalie pay her parents each week per week, Write a function that shows the relationship between the ​amount Natalie still owes, and the number of weeks she ​has paid,


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Answer 1

The answer is as follows

Explanation:

Natalie borrowed $180 from her parents. Over the course of 8 weeks, she paid back equal amounts every 2 weeks. We can find the amount she pays each week by finding the difference in the amount she owes between two consecutive weeks and dividing by 2.

For example, between week 0 and week 2, she paid back $180 - $162 = $18. Dividing by 2, we get $9 per week. Similarly, between week 2 and week 4, she paid back $162 - $144 = $18, so she pays $9 per week. We can do this for all the consecutive weeks to find the average amount she pays per week:

- Between week 0 and week 2: $9 per week

- Between week 2 and week 4: $9 per week

- Between week 4 and week 6: $9 per week

- Between week 6 and week 8: $9 per week

So Natalie pays her parents $9 per week.

To write a function that shows the relationship between the amount Natalie still owes and the number of weeks she has paid, we can use the formula:

Amount owed = $180 - $9 * (number of weeks paid)

or

Amount owed = $180 - $9x

where x is the number of weeks paid.