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If x, y, and z are all positive integers, what is the least common mul
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28 Aug 2018, 05:22
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If x, y, and z are all positive integers, what is the least common multiple of x, y, and z? (1) The least common multiple of x and y is 15. (2) The least common multiple of x and z is 18.
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Re: If x, y, and z are all positive integers, what is the least common mul
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28 Aug 2018, 05:28
From statement 1: No info about Z. Insufficient. From Statement 2: No info about Y. Insufficient. Combining Both: LCM of X and Y is 15. LCM of X and Z is 18. LCM of X, Y and Z is 9*5*2 = 90. Sufficient.. C is the answer.
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Re: If x, y, and z are all positive integers, what is the least common mul
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07 May 2019, 19:20
Bunuel wrote: If x, y, and z are all positive integers, what is the least common multiple of x, y, and z?
(1) The least common multiple of x and y is 15.
(2) The least common multiple of x and z is 18. BunuelLCM of xy = 15 => numbers can be 1x15, 5x3, LCM of xz = 18 => numbers can be 1x18, 9x2, 6x3 x is the common number, so the numbers be like 1, 15, 18. Can you please tell how to find the values of x, y ,z specifically ?



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Re: If x, y, and z are all positive integers, what is the least common mul
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07 May 2019, 20:28
Statement 1 LCM of xy = 15, we don't know the value of z insufficient Statement 2 The least common multiple of x and z is 18, we don't know the value of z insufficient Combining statement 1 and 2 x can be either 1 or 3 1. x=1, y=15 and z=18, LCM = 902. x=3, y=5 and z=18, LCM=903. x=3, y=15 and z=18 LCM=90Sufficient pandajee wrote: Bunuel wrote: If x, y, and z are all positive integers, what is the least common multiple of x, y, and z?
(1) The least common multiple of x and y is 15.
(2) The least common multiple of x and z is 18. BunuelLCM of xy = 15 => numbers can be 1x15, 5x3, LCM of xz = 18 => numbers can be 1x18, 9x2, 6x3 x is the common number, so the numbers be like 1, 15, 18. Can you please tell how to find the values of x, y ,z specifically ?



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Re: If x, y, and z are all positive integers, what is the least common mul
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08 May 2019, 10:06
nick1816 wrote: Statement 1 LCM of xy = 15, we don't know the value of z insufficient Statement 2 The least common multiple of x and z is 18, we don't know the value of z insufficient Combining statement 1 and 2 x can be either 1 or 3 1. x=1, y=15 and z=18, LCM = 902. x=3, y=5 and z=18, LCM=903. x=3, y=15 and z=18 LCM=90Sufficient pandajee wrote: Bunuel wrote: If x, y, and z are all positive integers, what is the least common multiple of x, y, and z?
(1) The least common multiple of x and y is 15.
(2) The least common multiple of x and z is 18. BunuelLCM of xy = 15 => numbers can be 1x15, 5x3, LCM of xz = 18 => numbers can be 1x18, 9x2, 6x3 x is the common number, so the numbers be like 1, 15, 18. Can you please tell how to find the values of x, y ,z specifically ? Thanks.. For all value of x & y having LCM as 15, z=18 will always give LCM of x,y,z as 90. So, we don't need to worry about xz being 1x18 or 9x2 or 6x3... right ?



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Re: If x, y, and z are all positive integers, what is the least common mul
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08 May 2019, 11:08
Exactly!! BTW you can't consider 6*3 because their LCM is 6 not 18
Thanks.. For all value of x & y having LCM as 15, z=18 will always give LCM of x,y,z as 90. So, we don't need to worry about xz being 1x18 or 9x2 or 6x3... right ?[/quote]



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If x, y, and z are all positive integers, what is the least common mul
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23 Jul 2019, 11:57
Bunuel wrote: If x, y, and z are all positive integers, what is the least common multiple of x, y, and z?
(1) The least common multiple of x and y is 15.
(2) The least common multiple of x and z is 18. Hi, BunuelI want to clear my concept on LCM; Suppose LCM of any set 'n' & set 'm' are given and if we are asked to find LCM of all the no.s of set n & m combined it will simply be LCM [LCM (set n), LCM (set m)] why? as LCM is the least such no. which is divisible by all the no.s of set n & m. If i'm wrong please clear my doubt!!
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If x, y, and z are all positive integers, what is the least common mul
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23 Jul 2019, 11:57






