Question

Forensic scientists can determine the approximate height that a male person was by measuring the length of the femur (thigh bone). They use the formula: height = 1.88f + 32.01, where f is the length of the femur in inches.

To the nearest inch, how many inches long is the femur of a male who is 71 inches tall?

166 inches
21 inches
20 inches
165 inches

Answer 1

To find the length of the femur for a male who is 71 inches tall using the formula provided, we can rearrange the formula \( \text{height} = 1.88f + 32.01 \) to solve for \( f \).

Starting with the original equation:

\[
\text{height} = 1.88f + 32.01
\]

Substituting the height (71 inches) into the equation:

\[
71 = 1.88f + 32.01
\]

Next, we will isolate \( f \) by first subtracting 32.01 from both sides:

\[
71 - 32.01 = 1.88f
\]

\[
38.99 = 1.88f
\]

Now, divide both sides by 1.88 to solve for \( f \):

\[
f = \frac{38.99}{1.88}
\]

Calculating this gives:

\[
f \approx 20.74
\]

To the nearest inch, the length of the femur is approximately \( 21 \) inches.

Therefore, the correct answer is:

**21 inches**