If the units digit of the three-digit positive integer k is nonzero, what is the tens digit of k?
(1) The tens digit of k + 9 is 3.
(2) The tens digit of k + 4 is 2.
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Morgoth
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IMO Abeater wrote:If the units digit of the three-digit positive integer k is nonzero, what is the tens digit of k?
(1) The tens digit of k + 9 is 3.
(2) The tens digit of k + 4 is 2.
statement (1)
let k = xyz [3 digit, unit digit non zero]
x y z
++9
____
x30
minimum value of z can be 1 since it is non zero integer.
1+9 = 10
1 carry over to the tens y+1 = 3 , y =2
maximum value of z can be 9
9+9 = 18
1 carry over to the tens y+1 = 3 , y =2
Sufficient.
Statement (2)
x y z
++4
____
x2(z+4)
z=1, 1+4 = 5, y=2
z=9, 9+4 = 13, 1 carry over, if y=1, tens digit will be 2. Insufficient.
Thus, A.
OA?
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gmatguy16
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can someone please explain how the oa is a,
if number =122 ,then 122+9 =131,tens digit is 3
if number =130, then 130+9=139 ,tens digit is 3 ,hence we have 2 different values of k ,2 and 3..did i mis u nderstood the question ?
if number =122 ,then 122+9 =131,tens digit is 3
if number =130, then 130+9=139 ,tens digit is 3 ,hence we have 2 different values of k ,2 and 3..did i mis u nderstood the question ?
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Morgoth
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Units digit of the number cannot be 0. Therefore minimum value of the units digit can be 1 and maximum value can be 9. Try with these two values, yu should get the answer.gmatguy16 wrote:can someone please explain how the oa is a,
if number =122 ,then 122+9 =131,tens digit is 3
if number =130, then 130+9=139 ,tens digit is 3 ,hence we have 2 different values of k ,2 and 3..did i mis u nderstood the question ?
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gmattakers
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aj5105
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IMO A
BTW neat expl !
BTW neat expl !
Morgoth wrote:IMO Abeater wrote:If the units digit of the three-digit positive integer k is nonzero, what is the tens digit of k?
(1) The tens digit of k + 9 is 3.
(2) The tens digit of k + 4 is 2.
statement (1)
let k = xyz [3 digit, unit digit non zero]
x y z
++9
____
x30
minimum value of z can be 1 since it is non zero integer.
1+9 = 10
1 carry over to the tens y+1 = 3 , y =2
maximum value of z can be 9
9+9 = 18
1 carry over to the tens y+1 = 3 , y =2
Sufficient.
Statement (2)
x y z
++4
____
x2(z+4)
z=1, 1+4 = 5, y=2
z=9, 9+4 = 13, 1 carry over, if y=1, tens digit will be 2. Insufficient.
Thus, A.
OA?
