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The product of 3305 and the 1digit integer x is a 5digit integer. Th
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27 May 2017, 19:39
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The Official Guide for GMAT Quantitative Review 2018Practice QuestionQuestion No.: PS 89 Page: 72 The product of 3305 and the 1digit integer x is a 5digit integer. The units (ones) digit of the product is 5 and the hundreds digit is y. If A is the set of all possible values of x and B is the set of all possible values of y, then which of the following gives the numbers of A and B? AB (A) {1, 3, 5, 7, 9}{0, 1, 2, 3, 4, 5, 6, 7, 8, 9} (B) {1, 3, 5, 7, 9}{1, 3, 5, 7, 9} (C) {3, 5, 7, 9}{1, 5, 7, 9} (D) {5, 7, 9}{1, 5, 7} (E) {5, 7, 9}{1, 5, 9}
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Re: The product of 3,305 and the 1digit integer xis a 5digit integer. Th
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23 Jul 2017, 15:11
carcass wrote: The product of 3,305 and the 1digit integer x is a 5digit integer. The units (ones) digit of the product is 5 and the hundreds digit is y. If A is the set of all possible values of x and B is the set of all possible values of y, then which of the following gives the members of A and B?
A AND B
A. {1,3,5,7,9} (0,1,2,3,4,5,6,7,8,9}
B. {1,3,5,7,9} {1,3,5,7,9}
C. {3,5,7,9} {1,5,7,9}
D. {5,7,9} {1,5,7}
E. {5,7,9} {1,5,9} Wow. There are a lot of steps to this one. The key is going to be extremely careful organization (you should pick up on that when you see how many numbers there are in the answer choices, and the complexity of the question they're asking you.) First, I read the whole thing. Then I approached the first sentence: 3305x is a 5digit integer. That probably limits the possible values for x. For instance, x can't be 1, 2, or 3, because the product would be too small. Is there an upper limit to the values of x? For instance, could x be 9? To check, I multiplied 3305*9 on my paper and found that the result had 5 digits. So, the acceptable values for x will be 4, 5, 6, 7, 8, and 9 (so far). I jotted those down on my scratch paper (large & clear). 4 5 6 7 8 9 The problem also says that the units digit of 3305x is 5. That means x must be odd. If x was even, the units digit would come out to 0. So, I crossed off all of the even numbers: 4 5 6 7 8 9 Now there are only three possible values for x. I don't see anything that limits it further than that, so I write down on my paper: A = {5, 7, 9} At this point, I also jot down the answer choices, A B C D E, and cross off everything except for D and E. To figure out the values of y, we need to find the hundreds digit of 3305x. There's a rule that says that if you only want a particular digit, you can ignore everything past that digit. We can ignore the first 3 in 3305 and just treat it like 305, since it won't affect the hundreds digit of the result. That'll speed up the multiplication. 305 * 5 = 1525, hundreds digit = 5 305 * 7 = 2135, hundreds digit = 1 305 * 9 = 2745, hundreds digit = 7 So now I know B = {1, 5, 7}. Finally, check this against the two remaining answer choices. D is correct.
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The product of 3,305 and the 1digit integer xis a 5digit integer. Th
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23 Jul 2017, 12:30
The product of 3,305 and the 1digit integer x is a 5digit integer. The units (ones) digit of the product is 5 and the hundreds digit is y. If A is the set of all possible values of x and B is the set of all possible values of y, then which of the following gives the members of A and B? A AND BA. {1,3,5,7,9} (0,1,2,3,4,5,6,7,8,9} B. {1,3,5,7,9} {1,3,5,7,9} C. {3,5,7,9} {1,5,7,9} D. {5,7,9} {1,5,7} E. {5,7,9} {1,5,9}
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Re: The product of 3,305 and the 1digit integer xis a 5digit integer. Th
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09 Aug 2017, 12:43
carcass wrote: The product of 3,305 and the 1digit integer x is a 5digit integer. The units (ones) digit of the product is 5 and the hundreds digit is y. If A is the set of all possible values of x and B is the set of all possible values of y, then which of the following gives the members of A and B?
A AND B
A. {1,3,5,7,9} (0,1,2,3,4,5,6,7,8,9}
B. {1,3,5,7,9} {1,3,5,7,9}
C. {3,5,7,9} {1,5,7,9}
D. {5,7,9} {1,5,7}
E. {5,7,9} {1,5,9} We are given that the product of 3,305 and the 1digit integer x is a 5digit integer, the units (ones) digit of the product is 5, and the hundreds digit is y. In order for the product to be a 5digit integer, we see that x cannot be 1, 2, or 3. In order for the product to have 5 as its ones digit, we can also eliminate 4, 6, and 8 from consideration. Thus, x can only be 5, 7, or 9. Let’s now solve for y: When x is 5, since 5 x 3,305 = 16,525, y is 5. When x is 7, since 7 x 3,305 = 23,135, y is 1. When x is 9, since 9 x 3,305 = 29,745, y is 7. Thus, A = 5, 7, and 9 and B = 1, 5, and 7. Answer: D
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Re: The product of 3,305 and the 1digit integer xis a 5digit integer. Th
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10 Sep 2017, 04:03
carcass wrote: The product of 3,305 and the 1digit integer x is a 5digit integer. The units (ones) digit of the product is 5 and the hundreds digit is y. If A is the set of all possible values of x and B is the set of all possible values of y, then which of the following gives the members of A and B?
A AND B
A. {1,3,5,7,9} (0,1,2,3,4,5,6,7,8,9}
B. {1,3,5,7,9} {1,3,5,7,9}
C. {3,5,7,9} {1,5,7,9}
D. {5,7,9} {1,5,7}
E. {5,7,9} {1,5,9} _ _ Y _ 5 = 3305 x X we know x cannot equal 1 or 3 because the product of that does not equal 5 digits, but only 4 therefore eliminate answers a,b,c for x, we are left with 5,7,9  just plug these in for x 3305 x 5 = 16,525 wherein y = 5 3305 x 7 = 23,135 wherein y = 1 3305 x 9 = 29,745 wherein y = 7 therefore the answer is D hope that helps



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Re: The product of 3305 and the 1digit integer x is a 5digit integer. Th
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27 May 2017, 20:55
hazelnut wrote: The Official Guide for GMAT Quantitative Review 2018Practice QuestionQuestion No.: PS 89 Page: 72 The product of 3305 and the 1digit integer x is a 5digit integer. The units (ones) digit of the product is 5 and the hundreds digit is y. If A is the set of all possible values of x and B is the set of all possible values of y, then which of the following gives the numbers of A and B? AB (A) {1, 3, 5, 7, 9}{0, 1, 2, 3, 4, 5, 6, 7, 8, 9} (B) {1, 3, 5, 7, 9}{1, 3, 5, 7, 9} (C) {3, 5, 7, 9}{1, 5, 7, 9} (D) {5, 7, 9}{1, 5, 7} (E) {5, 7, 9}{1, 5, 9} 3305*A = xxBxx option A,B,C are out as 3305 multiplied by 1 or 3 (which set A contains) never gives a 5 digit product value working further (D) 3305*5 = 16 525 3305*7 = 23 121 3305*9 = 29 745 so Set B contains all three above values Ans D



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Re: The product of 3,305 and the 1digit integer xis a 5digit integer. Th
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24 Jun 2018, 06:40
adkikani wrote: niks18 chetan2u VeritasPrepKarishma Can I skip calculation part as shown by JeffTargetTestPrepknowing that 9*9 = 81 ? All individual set elements must result in product as 5 in unit digit. Hi adkikaniOnce you have identified the elements of set x, then only two options remain D & E. concentrate on the last three digits of the number 3 305 when you multiply 05 by x, then the product will not have any carry over for the hundred's digit. for e.g 05*9=45 and there is no carry forward. Hence the hundreds digit of the resulting product will be simply unit's digit of 3*x so y = 3*5=1 5y=3*7=2 1 & y=3*9=2 7so you can save yourself from calculation if you have visualized this step



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Re: The product of 3,305 and the 1digit integer xis a 5digit integer. Th
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29 Nov 2018, 12:40
carcass wrote: The product of 3,305 and the 1digit integer x is a 5digit integer. The units (ones) digit of the product is 5 and the hundreds digit is y. If A is the set of all possible values of x and B is the set of all possible values of y, then which of the following gives the members of A and B?
A AND B
A. {1,3,5,7,9} (0,1,2,3,4,5,6,7,8,9}
B. {1,3,5,7,9} {1,3,5,7,9}
C. {3,5,7,9} {1,5,7,9}
D. {5,7,9} {1,5,7}
E. {5,7,9} {1,5,9} Dear Moderator, This same question seems to have been duplicated in the link below, you may wish to merge the same, Thank you. https://gmatclub.com/forum/theproduct ... l#p1859424
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Re: The product of 3,305 and the 1digit integer xis a 5digit integer. Th
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30 Jul 2017, 07:31
looks difficult .. but easy equation to solve . So challenge if any will be the language of the question .
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The product of 3,305 and the 1digit integer xis a 5digit integer. Th
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03 Aug 2017, 08:55
ccooley wrote: carcass wrote: The product of 3,305 and the 1digit integer x is a 5digit integer. The units (ones) digit of the product is 5 and the hundreds digit is y. If A is the set of all possible values of x and B is the set of all possible values of y, then which of the following gives the members of A and B?
A AND B
A. {1,3,5,7,9} (0,1,2,3,4,5,6,7,8,9}
B. {1,3,5,7,9} {1,3,5,7,9}
C. {3,5,7,9} {1,5,7,9}
D. {5,7,9} {1,5,7}
E. {5,7,9} {1,5,9} Wow. There are a lot of steps to this one. The key is going to be extremely careful organization (you should pick up on that when you see how many numbers there are in the answer choices, and the complexity of the question they're asking you.) First, I read the whole thing. Then I approached the first sentence: 3305x is a 5digit integer. That probably limits the possible values for x. For instance, x can't be 1, 2, or 3, because the product would be too small. Is there an upper limit to the values of x? For instance, could x be 9? To check, I multiplied 3305*9 on my paper and found that the result had 5 digits. So, the acceptable values for x will be 4, 5, 6, 7, 8, and 9 (so far). I jotted those down on my scratch paper (large & clear). 4 5 6 7 8 9 The problem also says that the units digit of 3305x is 5. That means x must be odd. If x was even, the units digit would come out to 0. So, I crossed off all of the even numbers: 4 5 6 7 8 9 Now there are only three possible values for x. I don't see anything that limits it further than that, so I write down on my paper: A = {5, 7, 9} At this point, I also jot down the answer choices, A B C D E, and cross off everything except for D and E. To figure out the values of y, we need to find the hundreds digit of 3305x. There's a rule that says that if you only want a particular digit, you can ignore everything past that digit. We can ignore the first 3 in 3305 and just treat it like 305, since it won't affect the hundreds digit of the result. That'll speed up the multiplication. 305 * 5 = 1525, hundreds digit = 5 305 * 7 = 2135, hundreds digit = 1 305 * 9 = 2745, hundreds digit = 7 So now I know B = {1, 5, 7}. Finally, check this against the two remaining answer choices. D is correct. If I am a 600650 scorer , then is it possible to solve this question in just 2 minutes?



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Re: The product of 3,305 and the 1digit integer xis a 5digit integer. Th
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01 Sep 2017, 04:16
"The product of 3,305 and the 1digit integer x is a 5digit integer"
It is slightly confusing. I thought, above statement meant, product of three integers i.e. 3, 305 and another integer x.



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Re: The product of 3,305 and the 1digit integer xis a 5digit integer. Th
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10 Sep 2017, 04:04
nareshlawadia wrote: "The product of 3,305 and the 1digit integer x is a 5digit integer"
It is slightly confusing. I thought, above statement meant, product of three integers i.e. 3, 305 and another integer x. When you are translating english to math, "product" means multiplication, and "is" translates to equals sign so 3,305 x X = a five digit integer hope that helps



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Re: The product of 3,305 and the 1digit integer xis a 5digit integer. Th
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24 Jun 2018, 05:33
niks18 chetan2u VeritasPrepKarishma Can I skip calculation part as shown by JeffTargetTestPrepknowing that 9*9 = 81 ? All individual set elements must result in product as 5 in unit digit.
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Re: The product of 3305 and the 1digit integer x is a 5digit integer. Th
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13 Aug 2018, 07:18
If we look at the given answer, we can see than 5 digit number is possible for values of A greater than 3. So we are only left with option C and D. now by working further, we have to determine whether we can get hundreds digit 9 or 7. so if we multiply 3305 by 5 we get 16525 and hundreds digit is 5 if we multiply 3305 by 7 we get 22135 and hundreds digit is 1 if we multiply 3305 by 9 we get 29745 and hundreds digit is 7as 5,1 and 7 are members of set B in option (D) so Answer is (D)
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Re: The product of 3305 and the 1digit integer x is a 5digit integer. Th
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13 Aug 2018, 07:27
hazelnut wrote: The Official Guide for GMAT Quantitative Review 2018Practice QuestionQuestion No.: PS 89 Page: 72 The product of 3305 and the 1digit integer x is a 5digit integer. The units (ones) digit of the product is 5 and the hundreds digit is y. If A is the set of all possible values of x and B is the set of all possible values of y, then which of the following gives the numbers of A and B? AB (A) {1, 3, 5, 7, 9}{0, 1, 2, 3, 4, 5, 6, 7, 8, 9} (B) {1, 3, 5, 7, 9}{1, 3, 5, 7, 9} (C) {3, 5, 7, 9}{1, 5, 7, 9} (D) {5, 7, 9}{1, 5, 7} (E) {5, 7, 9}{1, 5, 9} The product of 3305 and the 1digit integer x is a 5digit integer. 3305*3 = 9915 So x is 4 or more. Since x is a 1 digit integer, it can be anything from 4 to 9. If units digit of the product is 5, this means x must be odd (if x were even, the units digit will be 0) So x must be 5/7/9 3305 * 5 = ...525 3305 * 7 = ...135 3305 * 9 = ...745 So the hundreds digit would be 5/1/7 (value of y) Answer (D)
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Re: The product of 3,305 and the 1digit integer xis a 5digit integer. Th
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25 Oct 2018, 08:05
carcass wrote: The product of 3,305 and the 1digit integer x is a 5digit integer. The units (ones) digit of the product is 5 and the hundreds digit is y. If A is the set of all possible values of x and B is the set of all possible values of y, then which of the following gives the members of A and B?
A AND B
A. {1,3,5,7,9} (0,1,2,3,4,5,6,7,8,9}
B. {1,3,5,7,9} {1,3,5,7,9}
C. {3,5,7,9} {1,5,7,9}
D. {5,7,9} {1,5,7}
E. {5,7,9} {1,5,9} To understand this we need to keep this thought in mind that x > 4 because 3,305 * 3 is less than 5 digits. Since the ones digit is 5 that means x has to be an odd integer greater than 4. These are 5,7, and 9. Now we are concerned with hundreds digit. We can take 300 * 5 = 1,500 300 * 7 = 2,100 and 300 * 9 = 2,700 So we get 1,5, and 7 Answer choice D



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Re: The product of 3,305 and the 1digit integer xis a 5digit integer. Th
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29 Nov 2018, 12:51
stne wrote: carcass wrote: The product of 3,305 and the 1digit integer x is a 5digit integer. The units (ones) digit of the product is 5 and the hundreds digit is y. If A is the set of all possible values of x and B is the set of all possible values of y, then which of the following gives the members of A and B?
A AND B
A. {1,3,5,7,9} (0,1,2,3,4,5,6,7,8,9}
B. {1,3,5,7,9} {1,3,5,7,9}
C. {3,5,7,9} {1,5,7,9}
D. {5,7,9} {1,5,7}
E. {5,7,9} {1,5,9} Dear Moderator, This same question seems to have been duplicated in the link below, you may wish to merge the same, Thank you. https://gmatclub.com/forum/theproduct ... l#p1859424Topics merged. Thank you.
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Re: The product of 3,305 and the 1digit integer xis a 5digit integer. Th
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