Transcript EPSY 602

EPSY 602
Problems
Fall 2004
Cryptarithmetic Problem
Problem
BEST
+ MADE
MASER
Treat this as an addition problem.
Change letters to numbers such that
constraints represented in the
problem are satisfied. The 8 different
letters that can take on any value
from 0 to 9, but no letter can assume
more than one value.
Solution
July 18, 2015
Copyright © 2004 - Robert J. Hall
2
Algebra Word Problem
A candle factory has two workers, Jones
and Smith. Jones makes candles at the
rate of 60 per hour and Smith makes 75
candles per hour. Jones spends one hour
more than Smith each day making
candles. If Jones makes the same
number of candles each day as Smith,
how long does Smith work?
Solution
July 18, 2015
Copyright © 2004 - Robert J. Hall
3
Word Puzzles
MOMANON
PRICE
EGAMI
AMY
TERTHENET
33 CO.
MAKE MNN
NOBODY’S
THE LAW
Solution
July 18, 2015
Copyright © 2004 - Robert J. Hall
4
Summary



Using specific operators and observing constraints,
the problem solver moves from an initial state to a
goal state.
In well-defined problems, the initial state and the goal
are explicit from the onset.
In ill-defined problems; the problem solver must first
identify the states.


Knowledge-lean problems require relatively little domain
knowledge.
Knowledge-rich problems require much domain knowledge.
July 18, 2015
Copyright © 2004 - Robert J. Hall
5
Cryptarithmetic Problem
B EST
+ MADE
MASER
1
1
1
9567
+ 1085
10652
• The first letter to be assigned a number would be ‘M.’ ‘M’ can
only be the result of a carry and therefore must equal 1.
• With ‘M’ equal to 1, ‘B’ would have to equal 8 or 9 to effect the
carry. If ‘B’ equals 8 or 9, then ‘A’ equals 0.
• With ‘A’ equal to 0, we know that ‘S’ equals ‘E’ + 1 (carried
from the 10s column. We also know that ‘S’ + ‘D’ equals ‘E’
which means that ‘D’ would have to equal 8 or 9 depending
on the number assigned to ‘B’ and that if ‘D’ equals 8 there
must be a carry from the 1s column.
• ‘B’ has to be 9 because if ‘B’ equals 8 then ‘D’ would have to
equal 9 then the ‘E’ + ‘A’ (0) = ‘S’ would not result in the carry
that would be necessary for the 1000s column.
• ‘B’ then equals 9, ‘D’ equals 8, ‘E’ equals 5, and ‘S’ equals 6.
That leaves ‘T’ and ‘R’. From the remaining numbers, ‘T’
would have to equal 7 and ‘R’ 2.With
Return
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Copyright © 2004 - Robert J. Hall
6
Algebra Word Problem
A candle factory has two workers, Jones and Smith. Jones makes candles at the rate of 60 per hour
and Smith makes 75 candles per hour. Jones spends one hour more than Smith each day making
candles. If Jones makes the same number of candles each day as Smith, how long does Smith work?
Let t = length of time Smith works
t + 1 = length of time Jones works
The length of time Smith works times 75, then, would equal the number
of candles that Smith produces and the length of time Jones works
times 60 would equal the number of candles that Jones produces.
To produce the same number of
60 (t + 1) = 75t
60 = 15t
candles per day Smith would work
4 hours and Jones would have to
60t + 60 = 75t
4=t
work 5 hours.
Return
July 18, 2015
Copyright © 2004 - Robert J. Hall
7
Word Puzzles
Frame Games
MOMANON
PRICE
MAN IN THE MOON
HALF PRICE
AMY
EGAMI
REVERSE IMAGE
BIGAMY
TERTHENET
33 CO.
THREE’S COMPANY
THE INTERNET
NOBODY’S
THE LAW
MAKE MNN
MAKE AMENDS
Return
July 18, 2015
NOBODY’S ABOVE THE LAW
Copyright © 2004 - Robert J. Hall
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