12c i) ii) iii) help (1 Viewer)

lolwot

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Can someone show me how they did these/your answers, I might of stuffed them up? :spzz:
 

Menomaths

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7 years?


(please someone say 'this' or 'i got that too')
 

Menomaths

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87500 = n/6*(66,000-1500+1500n)

87500 = n/6*(64,500+1500n)

10750n+250n^2 = 87500

250n^2 + 10750N - 87500 = 0

n = -50 or n = 7

n =/= -50 therefore n = 7
 

NFmusic1995

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i did a stupid mistake, i found it normally, then time'd it by 3.... instead of divding, meh lost 1 mark since working is there LOL
 

lolwot

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LOL I managed to find the first year one-third of her annual (not cumulative) salary equals $87500... 154 years. So like in the 154th year she saves exactly $87500 of her now $262500 salary. I blame the wording :(

but ii) is like 330796.93 ..right?
 

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