Hi guys, does the GMAT ask questions on base system?
For example: how would you write 2234 in base 4 to a number in base 7?
Questions on base system
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- Abhey Kharbanda
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That kind of question would be out of scope for the GMAT.Abhey Kharbanda wrote:Hi guys, does the GMAT ask questions on base system?
For example: how would you write 2234 in base 4 to a number in base 7?
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Hi Abhey Kharbanda,
All of the questions that you'll face on the Official GMAT are in base-10, so you won't have to worry about working in any other base. That's a rather interesting question to be asking - have you been working with practice materials that expected you to convert your math to a different base?
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All of the questions that you'll face on the Official GMAT are in base-10, so you won't have to worry about working in any other base. That's a rather interesting question to be asking - have you been working with practice materials that expected you to convert your math to a different base?
GMAT assassins aren't born, they're made,
Rich
- Abhey Kharbanda
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Thanks Rich, no I haven't been working on them but thought of asking it here[email protected] wrote:Hi Abhey Kharbanda,
All of the questions that you'll face on the Official GMAT are in base-10, so you won't have to worry about working in any other base. That's a rather interesting question to be asking - have you been working with practice materials that expected you to convert your math to a different base?
GMAT assassins aren't born, they're made,
Rich
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2234 in base 4Abhey Kharbanda wrote:Hi guys, does the GMAT ask questions on base system?
For example: how would you write 2234 in base 4 to a number in base 7?
(2 x 4^3) + (2 x 4^2) + (2 x 4) + 4 = 128 + 32 + 8 + 4 = 172 (Base 10)
In Base 7... Wasn't sure how to do this formulaically, so I just logically reasoned it out.
172 (Base 10) = (3 x 7^2) + (3 x 7) + 4 = 334 (Base 7)
800 or bust!
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Fortunately no.Abhey Kharbanda wrote:Hi guys, does the GMAT ask questions on base system?
For example: how would you write 2234 in base 4 to a number in base 7?
And even if you are asked one, you would be told in the question itself how to change from one base to another and then the question would be asked.
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edit
Last edited by Matt@VeritasPrep on Fri Apr 28, 2017 12:41 am, edited 1 time in total.
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There are a couple errors here, but the idea is right! Some bases are easier to convert than others (i.e. you don't really have to run them through base 10), but I don't see an obvious way of doing 4 to 7 directly.800_or_bust wrote:
2234 in base 4
(2 x 4^3) + (2 x 4^2) + (2 x 4) + 4 = 128 + 32 + 8 + 4 = 172 (Base 10)
In Base 7... Wasn't sure how to do this formulaically, so I just logically reasoned it out.
172 (Base 10) = (3 x 7^2) + (3 x 7) + 4 = 334 (Base 7)
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Should of course add explicitly again that BASE SYSTEMS ARE NOT TESTED ON THE GMAT AS OF 2016.
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... which is a shame, because they're great fun (hint hint, GMAC! )
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Still holding out hope for these in GMAT 2017 ...Matt@VeritasPrep wrote:... which is a shame, because they're great fun (hint hint, GMAC! )
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... though the newer inequalities and quadratics and whatever else are cool too
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There isn't any base system on the GMAT (yet!), but it does appear on the Indian CAT.
And just for fun, 2234 isn't a number in base 4, since base 4 only has the digits 0, 1, 2, and 3. That said, suppose we have 2233 in base 4, and we want to convert it to base 7. We know that
2233(base 4) = 2*4³ + 2*4² + 3*4¹ + 3 => 175(base 10)
Now we want to put 175 in base 7. We start with the highest power of 7 that has a multiple less than 175: in this case, 7², which has the multiple 3*7². 175 - 3*7² = 28, so we have 28 left over. 28 = 4*7¹, so we're set:
175(base 10) = 3*7² + 4*7¹ + 0 => 340(base 7)
And just for fun, 2234 isn't a number in base 4, since base 4 only has the digits 0, 1, 2, and 3. That said, suppose we have 2233 in base 4, and we want to convert it to base 7. We know that
2233(base 4) = 2*4³ + 2*4² + 3*4¹ + 3 => 175(base 10)
Now we want to put 175 in base 7. We start with the highest power of 7 that has a multiple less than 175: in this case, 7², which has the multiple 3*7². 175 - 3*7² = 28, so we have 28 left over. 28 = 4*7¹, so we're set:
175(base 10) = 3*7² + 4*7¹ + 0 => 340(base 7)
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We also could try something like this:
2233 (base 4) =>
2000 + 200 + 30 + 3 (base 4) =>
2*1000 + 2*100 + 3*10 + 3 (base 4)
Since 10� (base 4) = 4� (base 10), we can replace 1000 with 4³, 100 with 10², etc.
2233 (base 4) =>
2000 + 200 + 30 + 3 (base 4) =>
2*1000 + 2*100 + 3*10 + 3 (base 4)
Since 10� (base 4) = 4� (base 10), we can replace 1000 with 4³, 100 with 10², etc.