Answer:
The inverse of a square matrix A, denoted by A-1, is the matrix so that the product of A and A-1 is the Identity matrix.
Step-by-step explanation:
The answer is in the attachment
Company A : 13 + 30m.....where m = # of mattresses
company B : 15 + 28m.....where m = # of mattresses
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company A : cleaning 4 mattresses : 13 + 30(4) = 13 + 120 = 133
company B: cleaning 4 mattresses : 15 + 28(4) = 15 + 112 = 127
so company B would charge less
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company A : cleaning 7 mattresses : 13 + 30(7) = 223
company B: cleaning 7 mattresses: 15 + 28(7) = 211
so by using company B, u would save : 223 - 211 = $ 12
The complete question in the attached figure
<span>observing the graph we can say that the racing game is approximately 25% of the total
</span>so
if 1 hour is ----------------------> 100%
X-----------------------------25%
x=25/100------> 1/4=0.25 hours
convert to minutes
0.25*60---------> 15 minutes
the answer is 15 minutes