Given a rectangular prism labeled A with the dimensions l=2 , w=4 , and h=6 , and a second prism labeled B with the dimensions l=6 , w=12 , and h=18 , how many times larger will the surface area of prism B be than prism A ?(1 point) Prism B ’s surface area is times larger than the surface area of prism A .

1 answer

To find how many times larger the surface area of prism B is compared to prism A, we need to calculate the surface area of both prisms using the formula for the surface area of a rectangular prism:

\[ \text{Surface Area} = 2(lw + lh + wh) \]

Surface Area of Prism A

Given dimensions for prism A:

  • \( l = 2 \)
  • \( w = 4 \)
  • \( h = 6 \)

Calculating the surface area:

\[ \text{Surface Area of A} = 2(lw + lh + wh) = 2(2 \cdot 4 + 2 \cdot 6 + 4 \cdot 6) \]

Calculating each term:

  • \( lw = 2 \cdot 4 = 8 \)
  • \( lh = 2 \cdot 6 = 12 \)
  • \( wh = 4 \cdot 6 = 24 \)

Now summing these:

\[ 8 + 12 + 24 = 44 \]

Thus, the surface area of prism A is:

\[ \text{Surface Area of A} = 2 \cdot 44 = 88 \]

Surface Area of Prism B

Given dimensions for prism B:

  • \( l = 6 \)
  • \( w = 12 \)
  • \( h = 18 \)

Calculating the surface area:

\[ \text{Surface Area of B} = 2(lw + lh + wh) = 2(6 \cdot 12 + 6 \cdot 18 + 12 \cdot 18) \]

Calculating each term:

  • \( lw = 6 \cdot 12 = 72 \)
  • \( lh = 6 \cdot 18 = 108 \)
  • \( wh = 12 \cdot 18 = 216 \)

Now summing these:

\[ 72 + 108 + 216 = 396 \]

Thus, the surface area of prism B is:

\[ \text{Surface Area of B} = 2 \cdot 396 = 792 \]

Finding the Ratio

Now, to find how many times larger the surface area of prism B is than that of prism A:

\[ \text{Ratio} = \frac{\text{Surface Area of B}}{\text{Surface Area of A}} = \frac{792}{88} = 9 \]

Thus, prism B's surface area is 9 times larger than the surface area of prism A.

So, the answer is:

Prism B’s surface area is 9 times larger than the surface area of prism A.