A tailor can make a pair of pants from the scraps left over from sewing up five pairs of pants. If he has twenty-five scraps, how many pairs of pants can he make?
Six pairs of pants. He can make five initially, but once he’s done making five pairs of pants, he’ll have five remaining sets of scraps, meaning he can make an additional pair of pants, totaling six.
On a dark, stormy Halloween night, four kids named Luke, John, Sarah and Bob walk into a haunted house during a blackout. Only one can escape. They take a staircase to the second floor, a trapdoor on the left, then go up the ladder to the right, followed by a 28-foot slide to the basement through the mouth of a Giant Panda. In one corner of the murky cellar is a chainsaw, a dagger, a rope with a noose and an electric chair. Written on the wall in blood are the words, “Only one will survive – choose your death!” Bob takes the rope, Sarah picks up the dagger, John chooses the chainsaw and Luke uses the chair.
Jim and his wife Patty were sitting in bed together one evening while a thunderstorm raged outside. After a bolt of lightning followed by a loud clap of thunder, the lights went out. Jim stopped reading and went to sleep, but Patty continued reading in the dark. How did she do it?
Patty is blind and was reading a Braille book so she didn’t need the light to begin with. Of course this also meant she didn’t know Jim snuck downstairs to get some cookies, but we’ll just keep that quiet.
Putting the information in a table makes it easier to solve. We’ll use A for Angie, B for Brenda, T for truth and F (false) for lying.
S
M
T
W
Th
F
S
A
T
F
F
F
T
T
T
B
T
T
T
T
F
F
F
To begin with, there aren’t any days where both of them told the truth and lied the day before, so we know one of them must be lying.
So we have two options, either Angel is lying or Brenda is.
Option 1. Angel is lying.
In order for this to be the case, she needs to be lying today and telling the truth yesterday, so we need two days in a row with T F. And if Brenda is telling the truth, she would need two days with F T. That means we’re looking for two days that have
Angie: T F
Brenda: F T
Option 2. Brenda is lying.
This is just the reverse of the above, so we need to find:
Angie: F T
Brenda: T F
The only day that matches either of the two options is Thursday, and it’s option 2. Brenda is the liar.
