KarunMendiratta wrote:
Carcass wrote:
In the correctly-worked addition of the two-digit numbers below, each letter represents a different positive integer less than 10. Which of the following could represent the number
1SK?
XY+YY-------
1SKvf
I. 178
II. 134
III. 120
(A) I only
(B) II only
(C) III only
(D) I and II
(E) I, II, and III
XY can be written as 10X + Y
YY can be wtitten as 10Y + Y
Sum (1SK) = 10X + 12Y
Let's check the option choices;
I. 178 = 10X + 12YX = 9, Y =
8812 - NO
X = 8, Y =
9812 - NO
X = 7, Y = 9 - YESII. 134 = 10X + 12YX = 9, Y =
4412 - NO
X = 8, Y =
5412 - NO
X = 7, Y =
6412 - NO
X = 6, Y =
7412 - NO
X = 5, Y = 7 - YESIII. 120 = 10X + 12YX = 9, Y =
3012 - NO
X = 8, Y =
4012 - NO
X = 7, Y =
5012 - NO
X = 6, Y = 5 - YESHence, option E
The question says that "each letter represents a different positive integer." The problem with I. (178) is that if X=7 and Y=9 then that means S=7, which wouldn't work, right? Can someone explain what I am missing? Thanks!