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June 03, 2023, 03:51:08 pm

Author Topic: rounding?  (Read 3563 times)  Share 

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dani01

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rounding?
« on: October 25, 2019, 06:25:11 pm »
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hey i did standard maths today and for one of the question we had to find the BAC and then using another formula had to sub it in to find the time for BAC to reach 0.
when doing the BAC i got an answer of 0.088....
and i rounded it to 0.09 (the question did not specify and usually BAC is to two decimal places).
i then subbed it into the other formula and got an answer of six.

However if i used 0.088 i would have gotten 5h 52minutes.
so 8 minutes is quite the difference.
how would they mark this. I have been reading the discussion group and people have been rounding to all sort of decimal places 4, 2, 3 or using the answer function on the calculator- With all of these options giving slightly different answers.

Would I be deducted marks for rounding to 0.09, technically I didn't do anything wrong since BAC is always to 2 and question did not say. The question was 4 marks I believe. Also if I were to get deducted how many? just one?

RuiAce

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Re: rounding?
« Reply #1 on: October 25, 2019, 06:33:32 pm »
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To my knowledge, it somewhat depends on luck here. I'm afraid I've never found out official information on this issue :(

If I were to take a guess: You'd lose one mark for using a rounded value, but no more than 1 mark lost.

dani01

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Re: rounding?
« Reply #2 on: October 25, 2019, 06:37:59 pm »
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To my knowledge, it somewhat depends on luck here. I'm afraid I've never found out official information on this issue :(

If I were to take a guess: You'd lose one mark for using a rounded value, but no more than 1 mark lost.

damn fingers crossed for no mark lost and if its just one then its alright. I was looking at the marking guidelines for past papers and although a lot of the time they have (using the question as an example)  0.088... they end up rounding to 0.09 and carry that on.
oh well looks like I will have to wait and see i guess. thanks for your reply

RuiAce

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Re: rounding?
« Reply #3 on: October 25, 2019, 06:42:02 pm »
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damn fingers crossed for no mark lost and if its just one then its alright. I was looking at the marking guidelines for past papers and although a lot of the time they have (using the question as an example)  0.088... they end up rounding to 0.09 and carry that on.
oh well looks like I will have to wait and see i guess. thanks for your reply
Yeah, NESA don't seem to follow their own rules in the solutions. That's true.

Bearing that in mind, fingers crossed you don't get penalised at all. It's over now though - hope you did your best :)