Evaluate the expression 3mn if m=3 and n=7 please help me solve this problem and explain

Mathematics

2 answers:

Helga [31]3 years ago

7 0

3(3)(7)
3*3=9then 9*7 equals 63.
so the answer is 63

Vinil7 [7]3 years ago

6 0

Substitute 3 into the expression for m, and 7 into it for n. So 3mn = 3(3)(7) = 3 x 21 = 63.

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Refer to the diagram shown below.

The volume of the container is 10 m³, therefore
x*2x*h = 10
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The area of the sides is
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(30/x)*($6) = 180/x

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C = 20x² + 180/x

The minimum cost is determined by C' = 0.
That is,
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The second derivative of C is
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The total cost is
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Answer: $163.54