Math 1090.0
2.5: Application Problems with Matrices
Handout
1. Decrypt the message “-26 59 -18 44 -101 52 -25 70 -30 -12 12 12 48 -84 25 2 -20 27” using the
inverse of the encryption matrix
1
—2
3
A=-45-6.
—2
3
(space)
0
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9
R
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2
A
1
B
E
F G H
C D
2345678
J K L M N 0 P Q
10 11 12 13 14 15 16 17
ST U VWX Y Z
19 20 21 22 23 24 25 26
Hint: Put the message in the following form
B
—
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59
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70
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48
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25
2
—20
27
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Math 1090.003
2. A movie theater is showing two different movies. Tickets for the first movie cost $4.50 per
person while tickets for the second movie cost $7.50. The total ticket sales for the day was
for
$10,002. The second movie is newer than the first, so there were 100 more tickets
the first movie than for the second movie. How many tickets of each type of ticket were sold?
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Math 109o.OOa
3. Toshi met his friends at the coffee house. He bought a total of 12 items. The number of drinks
purchased was two more than the number of danishes. Each mocha latte cost $3.50, each cup
of regular coffee cost $2, and the danishes were $1.50 each. He spend a total of $27.50 for the
lattes, coffee and danishes. How many of each item did he purchase?
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