A right triangular pyramid XYZB is cut from cube as shown in figure. The side of cube is 16 cm. X, Y and Z are mid points of the edges of the cube. What is the total surface area (in cm2) of the pyramid?

A. $$48\left[ {\left( {\sqrt 3 } \right) + 1} \right]$$
B. $$24\left[ {4 + \left( {\sqrt 3 } \right)} \right]$$
C. $$28\left[ {6 + \left( {\sqrt 3 } \right)} \right]$$
D. $$32\left[ {3 + \left( {\sqrt 3 } \right)} \right]$$
Answer: Option D
Solution (By Examveda Team)
BX = BY = 8 cm∴ XY = YZ = XZ = 8√2

$$l$$2 = 82 - (4√2)2
$$l$$2 = 32
$$l$$ = 4√2
Total surface area = $$\frac{1}{2}$$ × Perimeter of base × $$l$$ + Area of base
= $$\frac{1}{2} \times 3 \times 8\sqrt 2 \times 4\sqrt 2 + \frac{{\sqrt 3 }}{4}{\left( {8\sqrt 2 } \right)^2}$$
= 96 + 32√3
= 32(3 + √3) cm2
Related Questions on Mensuration 3D
A. 1.057 cm3
B. 4.224 cm3
C. 1.056 cm3
D. 42.24 cm3
A sphere and a hemisphere have the same volume. The ratio of their curved surface area is:
A. $${2^{\frac{3}{2}}}:1$$
B. $${2^{\frac{2}{3}}}:1$$
C. $${4^{\frac{2}{3}}}:1$$
D. $${2^{\frac{1}{3}}}:1$$

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