Question

Mara ran 3 km north and then 4 km east. She will finish her run by running directly home. What was the total distance of her run?

A right triangle with side lengths 8 kilometers and 4 kilometers. A point at intersection of the side with length 3 kilometers and the hypotenuse is labeled Mara's House.
5 km
7 km
12 km
14 km

Answers

GPT-4o mini
To determine the total distance of Mara's run, we can break it down into the segments she ran and then find the straight-line distance back to her starting point (home).

1. **Segment 1**: Mara runs 3 km north.
2. **Segment 2**: She then runs 4 km east.

Now, we can visualize these two segments as forming a right triangle where:
- One leg is 3 km (north).
- The other leg is 4 km (east).

To find the distance directly back home (the hypotenuse of the triangle), we can use the Pythagorean theorem:

\[
c = \sqrt{a^2 + b^2}
\]

where:
- \( a = 3 \) km (north),
- \( b = 4 \) km (east).

Calculating this:

\[
c = \sqrt{(3^2) + (4^2)} = \sqrt{9 + 16} = \sqrt{25} = 5 \text{ km}
\]

Now, Mara's total distance run can be calculated by summing the distances of the three legs of her journey:

- First segment: 3 km north
- Second segment: 4 km east
- Third segment: 5 km back home

Total distance:

\[
3 \text{ km} + 4 \text{ km} + 5 \text{ km} = 12 \text{ km}
\]

Thus, the total distance of Mara's run is **12 km**.