Jill is planting a tree. She needs to dig a hole that is 2 feet deep for every 5 feet of tree height.

Question

How deep should she dig the hole if her tree is 18 feet tall?

? = 9 feet

? = 7.2 feet

? = 8.1 feet

? = 7.8 feet

Answer 1

To determine how deep Jill should dig the hole for her tree, we can use the ratio provided: 2 feet deep for every 5 feet of tree height.

First, we need to set up the proportion. If we let \( h \) be the hole depth for an 18-foot tall tree, we can set up the following relationship based on the ratio:

\[ \frac{h}{2} = \frac{18}{5} \]

Now we can cross-multiply to solve for \( h \):

\[ 5h = 2 \times 18 \]

Calculating the right side gives:

\[ 5h = 36 \]

Now, divide both sides by 5 to solve for \( h \):

\[ h = \frac{36}{5} = 7.2 \text{ feet} \]

Therefore, Jill should dig the hole 7.2 feet deep.

So the answer is:

? = 7.2 feet