Have a look at this thread - some people have pointed out the errors in Jeff Geha's solutions.
http://community.boredofstudies.org/showthread.php?t=45145
However I
think there were a couple of errors in mojako's corrections, for example Q6(c)(ii) should be 5.5 years instead of 5.6 - I'm not sure though, Maths isn't really my thing.
Could someone please post the correct answers, or tell us about the mistakes you've picked out?
edit: in Q6c) ii), 5.6 is correct - the difference was due to rounding (but both 5.5 and 5.6 are acceptable, right?) So all of mojako's corrections are right
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