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HELP PLEASE I NEED IT

HELP PLEASE I NEED IT-example-1
User NDraskovic
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Answer and explanation:

45

The formula for surface area of a box is


SA = 2(lw+lh+hw), where l is the length, h is the height, and w is the width.

In the diagram, the length is 5 ft, the height is 1 1/3 ft, and the width is 2 1/2 ft.

  • (Side note: If you ever have trouble remembering what side is the length, height, and width, simply remember that as lone as you at least have each term multiplied by the other term once and still multiply the 2, you'll still get the right answer, regardless of whether you know which side is which)

For the purpose of this problem, it'd be helpful to convert the mixed numbers to improper fractions:


2(1)/(2)=((2*2)+1)/(2)=(5)/(2)\\ \\ 1(1)/(3)=((1*3)+1)/(3)=(4)/(3)

Now, we can find the surface area by plugging everything into the equation:


SA=2((5*5/2)+(5*4/3)+(4/3*5/2))\\SA=2(25/2+20/3+10/3)\\SA=2(45/2)\\SA=45

User Akshay Shrivastav
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