when to round down and when to round up?

[LFTM]

In the 2008 vcaa exam 2, matrices module question 2a(ii) they rounded 421.46 students to 421 but in question 4 they rounded 41.7 students up to 42.
I'm confused

Thanks for any help.

[vexx]

In the 2008 vcaa exam 2, matrices module question 2a(ii) they rounded 421.46 students to 421 but in question 4 they rounded 41.7 students up to 42.
I'm confused

Thanks for any help.

you round to the closest figure they want you to.

421.46, it has .46 to being 421 and .54 to being 422, so it makes sense that if its to the whole number it would round down since .46 is closer to being 421..
same with 41.7 it is closer to being 42 than 41.

make sense?

[LFTM]

In the 2008 vcaa exam 2, matrices module question 2a(ii) they rounded 421.46 students to 421 but in question 4 they rounded 41.7 students up to 42.
I'm confused

Thanks for any help.

you round to the closest figure they want you to.

421.46, it has .46 to being 421 and .54 to being 422, so it makes sense that if its to the whole number it would round down since .46 is closer to being 421..
same with 41.7 it is closer to being 42 than 41.

make sense?

oh shit i just realised this is a really dumb question, nvm, it's been a long day.lol

[vexx]

Haha, i actually got a rounding thing wrong like this a few months back for the first time, i felt like such an idiot after realising >_>
so dont worry

[LFTM]

Haha, i actually got a rounding thing wrong like this a few months back for the first time, i felt like such an idiot after realising >_>
so dont worry

lol, i can't believe i didn't realise when i was typing it.
How about the thing where you can't round people/ animals up? I remember my teacher saying something about this.

[vexx]

Haha, i actually got a rounding thing wrong like this a few months back for the first time, i felt like such an idiot after realising >_>
so dont worry

lol, i can't believe i didn't realise when i was typing it.
How about the thing where you can't round people/ animals up? I remember my teacher saying something about this.

usually you should do the same in further, what i've done and its been fine so far. since its just says "round to the whole number" which should be fine if done correctly like above..

[LFTM]

Ok, thanks.

[milkcarton]

Hi LFTM,
            My teacher has taught me a simple rule of thumb when it comes to rounding up or down.
".5 or less, let it rest. More than .5, let it drive(to the next number, LOL)"

[stonecold]

With matrices, you obviously have to round, but you have to make sure after rounding you haven't ended up with more than what you started with.

i.e.  Say you have 100 cars at the beginning.  Then for the steady state you get 55.5 and 44.5.  You can't round them both up, because you will end up with 101 cars, which is wrong.  Just choose one to go up, and one to go down.

This typically happens when you have a 3 or more state matrix.  If you round everything like normal, you may end up with too many or too few, so round the highest ones up and the lowest ones down, then depending one what is left in between, round it appropriately to make sure you don't evolve or lose numbers.