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1. Question is: Convert the two base-10 numbers 239 and 574 to base 4 and add them in base 4. Convert the sum back to base 10 and hence check your answer.

So, I've got:

and through long division. Then adding together I get , but when converting back to base ten, I get an answer of , which clearly isn't 239+574! I've double checked my arithmetic but I just can't see where I've messed up. Any help please?
2. Anybody?
3. (Original post by flown_muse)
So, I've got:

That's not correct for starters. Not looked at the rest yet.

Edit. And neither is the second one.

Spoiler:
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Post working if you're not able to get the values in the spoiler.

As a check once you've converted a number to base 4, you could convert it straight back to base 10 and see if you get the original value.
4. (Original post by ghostwalker)
That's not correct for starters. Not looked at the rest yet.

Edit. And neither is the second one.

Spoiler:
Show

Post working if you're not getting the values in the spoiler.
I've got 239, divide by 4, 59 r 3. Then 59 by 4, 14 r 3, 3 r 2, 0 r 2. Read remainders upwards, 2233.
5. (Original post by flown_muse)
I've got 239, divide by 4, 59 r 3. Then 59 by 4, 14 r 3, 3 r 2, 0 r 2. Read remainders upwards, 2233.
239, divide by 4, 59 r 3.

59 by 4, 14 r 3

14 by 4, 3 r 2

3 by 4 = 0 r 3
6. (Original post by ghostwalker)
239, divide by 4, 59 r 3.

59 by 4, 14 r 3

14 by 4, 3 r 2

3 by 4 = 0 r 3
Omg. I'm so sorry, I always do stupid stuff like this. But thank you, I've got it now, it's just my stupid stuff as usual. I managed to fix the other one too, I started dividing by 3 halfway through then switched to 4 again.

Bed time I think!

Thanks again.
7. (Original post by flown_muse)
Omg. I'm so sorry, I always do stupid stuff like this. But that you, I've got it now, it's just my stupid stuff as usual. I managed to fix the other one too, I started dividing by 3 halfway through then switched to 4 again.

Bed time I think!

Thanks again.
I notice you were starting to abbreviate your working towards the end. Perhaps that may have facilitated you going wrong. Just a thought.

Sweet dreams.

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