Question

Jason has already read 27 pages of a book. He plans to read 3 pages of the book every day. If f(n) represents the total number of pages that Jason will complete reading in n days, which of the following functions represents the relationship between f(n) and n?

A. f(n) = 27n - 3

B. f(n) = 3n - 27

C. f(n) = 27n + 3

D. f(n) = 3n + 27

Answer 1

PLZ i need help

Answer 2

Day 0: 27 pages (this is what we start with)


Day 1: 27+3 = 30 pages (end of day 1, add 3 pages)


Day 2: 27+3+3 = 33 pages (end of day 2, add 3 more pages)


Day 3: 27+3+3+3 = 36 pages (end of day 3, add 3 more pages)


Day 4: 27+3+3+3+3 = 39 pages (end of day 3, add 3 more pages)


etc etc

Answer 3

So how many pages are read on Day n?

Answer 4

3

Answer 5

that's the number of pages added per day

I'm asking how many pages total are read on day n?

Answer 6

what it day n

Answer 7

How many times did we add 3 for day 1?

Answer 8

1

Answer 9

How many times did we add 3 for day 2?

Answer 10

would the answer be C

Answer 11

How many times did we add 3 for day 2?

Answer 12

on day 2 we added 2 and on day 3 we added 3 and on day 4 we added 4

Answer 13

Good. So on any day, call it day x, we add 3 a total of x times

3+3+3+....+3 <--- Adding up 3...x number of times

we shorten this up to 3x (3 times x)

Then we add on 27, which is the base number we already started with to get 3x + 27

Answer 14

Now because they're using n in place of x, we just replace x with n to get this final answer

f(n) = 3n + 27

Answer 15

As confirmation, you can plug in say n = 2 (for day 2) to get

f(n) = 3n + 27

f(2) = 3*2 + 27

f(2) = 6 + 27

f(2) = 33

And it matches up with the info above

Answer 16

so the answer would be D

Answer 17

Correct

Answer 18

thank you

Answer 19

you're welcome