July 2022
Problem of the Month
Jean and Jane
by Sherry Widstrom
Jane never lies on Monday, Tuesday, Wednesday, and Thursday.
Jean always tells the truth on Monday, Friday, Saturday, and Sunday.
On the rest of the days, they may tell the truth or they may lie.
Both said that they lied yesterday.
What day is today?
Solution:
Today is Friday.
Jane is lying (she told the truth on Thursday), and Jean is telling the truth (as she always does on Friday).
Look at the table below:
|
|
S
|
M
|
T
|
W
|
T
|
F
|
S
|
| Jane
|
|
T
|
T
|
T
|
T
|
|
|
| Jean
|
T
|
T
|
|
|
|
T
|
T
|