Series Question? (1 Viewer)

[Alex499]

ok I know this is a little (ok way) late but I need help with this question on series. I'm doing Question 10 of 2001 and I get all the way to the end and get this line.

Bn = 1000(1.06)^n - 1200(1.06^n - 1)

Right and then the next line is
Therefore Bn = 1200 - 200(1.06)^n

What? where's the 200 come from?

oh god i'm so screwed

 

[danz90]

ok I know this is a little (ok way) late but I need help with this question on series. I'm doing Question 10 of 2001 and I get all the way to the end and get this line.

Bn = 1000(1.06)^n - 1200(1.06^n - 1)

Right and then the next line is
Therefore Bn = 1200 - 200(1.06)^n

What? where's the 200 come from?

oh god i'm so screwed

I remember doing this question.
Initially, I couldn't get it.

But then I started it again, manipulated the equation around etc and finally got the answer. Just keep manipulating, playing around with the equation until u get to their result. I remember this took me a lot of lines of working.

No, ur not screwed dude Remember, there are a large number of 2unit candidates that won't get more than like 2 or 3 marks in Q10.

 

[UncoKane]

Omg I totally did this question today Alex!

And I got 6 for that whole section.

brb getting the piece of paper.

 

[UncoKane]

$Bn = 1000(1.06)^n - 72(1.06^n - 1)/0.06
$Bn = 1000(1.06)^n - 1200(1.06^n - 1)

- 1200(1.06^n - 1) expands to - 1200(1.06)^n + 1200:

$Bn = 1000(1.06)^n - 1200(1.06)^n + 1200
$Bn = 1200 - 200(1.06)^n

I skipped a lot of steps because I cbf.

I don't think that helps haha sorry.

 

[stormz89]

because 1000-1200 = -200

Read it carefully.

 

[Alex499]

haha thanks kane. I asked yahoo answers too and they gave me the answer hahaha
yay yahoo answers
And thanks Danz90 but it's not only question 10. It's like questions 1,2,3,4,5,6,7,8,9 and 10.
yeah screwed