Geometry

Help Questions

6th Grade Math › Geometry

Questions 1 - 3

1

Hydraulic fracturing is a process used by gas companies to rupture and collects pockets of gas trapped within pockets of shale rock. A particular shale fracking site is $\frac{3}{4}\textup{ miles}$ in length and occupies an area of $\frac{1}{2}\textup{ miles}^2$ . How wide is this particular site?

$\frac{2}{3}\textup{ miles}$

$\frac{1}{3}\textup{ miles}$

$1\textup{ mile}$

$2\textup{ miles}$

Explanation

In order to solve this question, we need to first recall how to find the area of a rectangle.

$\text{Area}=\text{Length} \times \text{Width}$

Substitute in the given values in the equation and solve for $\text{Width}$ .

$\frac{1}{2}\ miles^2=\frac{3}{4}\ miles\times Width$

Divide both sides by $\frac{3}{4}\ miles$

$\frac{\frac{1}{2}\ miles^2}{\frac{3}{4}\ miles}=\frac{\frac{3}{4}\ miles \times Width}{\frac{3}{4}\ miles}$

Dividing by a fraction is the same as multiplying by its inverse or reciprocal.

Find the reciprocal of $\frac{3}{4}\ miles$

$\frac{3}{4}\ miles\rightarrow \frac{4}{3}\ miles$

Simplify and rewrite.

$Width=\frac{4}{3} \times \frac{1}{2}$

Multiply and solve.

$Width=\frac{4}{6}$

Reduce.

$Width=\frac{2}{3}\ miles$

The width of the fracking site is

2

What is the area of the right triangle in the following figure?

$58.5\textup{ in}^2$

$80\textup{ in}^2$

$65.5\textup{ in}^2$

$117\textup{ in}^2$

Explanation

In order to solve this problem, we need to recall the formula for area of a right triangle:

$A=\frac{1}{2}(l\times w)$ or $A=\frac{l\times w}{2}$

Now we can substitute in our side lengths from the question:.

$A=\frac{13\times9}{2}$

$A=\frac{117}{2}$

3

What is the volume of the rectangular prism in the following figure?

$140\textup{ cm}^3$

$146.5\textup{ cm}^3$

$144\textup{ cm}^3$

$138.5\textup{ cm}^3$

Explanation

The formula used to find volume of a rectangular prism is as follows:

$A=l\times w\times h$

Substitute our side lengths:

$A=3\frac{1}{2}\times4\times10$

$A=140\textup{ cm}^3$

Remember, volume is always written with cubic units because volume is how many cubic units can fit inside of a figure.

Return to subject