Question

What will be the volume of this doll house?

• A. $12000$ cm${}^3$
• B. $10000$ cm${}^3$
• C. $12000$ cm${}^3$
• D. None of the above

Answer 1

The correct option is A $12000$ cm${}^3$

The doll house comprises of a triangular prism mounted on a rectangular prism so we will calculate the volume of the two shapes separately.

For the triangular prism,
Height $=h=30$ cm
Base $=b=10$ cm
Area $=\frac{1}{2}\times h\times b$

$=\frac{1}{2}\times 30\times 10$

$=\frac{1}{2}\times 300=\frac{300}{2}=150$ cm${}^2$

$\therefore$ Volume $=$ area of the triangle $\times$ length of the prism
$=150\times 40=6000$ cm${}^3$

For the rectangular prism,
Length $l=15$ cm
Breadth $b=10$ cm
Area $=l\times b=15\times 10=150$ cm${}^2$

$\therefore$ Volume $=$ area of rectangle $\times$ length of the prism
$=150\times 40=6000$ cm${}^3$

$\therefore$ Volume of this model doll house $=6000+6000=12000$ cm${}^3$

Option (a.) is correct.