The following stem-and-leaf plot is constructed using data collected from the speed (km/h) of cars passing through an intersection. Data values were rounded to one decimal place.
Stem	Leaf
50	3
51	4
52	0      1      4
53	2      4      4      7      8
54	1      1      4      4      7      8      9
55	0      1      6
Key: 50 | 3 = 50.3 km/h
a. How many cars were sampled?
b. How many cars traveled through the intersection at 54.1 km/h?
c. What is the highest speed (km/h) recorded?
d. Is the distribution skewed positively or negatively?

Let's analyze the stem-and-leaf plot and answer each question step by step:

### Given Data (Speed in km/h):
- **Stem (50s)**: 50 | 3 (i.e., 50.3)
- **Stem (51s)**: 51 | 4 (i.e., 51.4)
- **Stem (52s)**: 52 | 0, 1, 4 (i.e., 52.0, 52.1, 52.4)
- **Stem (53s)**: 53 | 2, 4, 4, 7, 8 (i.e., 53.2, 53.4, 53.4, 53.7, 53.8)
- **Stem (54s)**: 54 | 1, 1, 4, 4, 7, 8, 9 (i.e., 54.1, 54.1, 54.4, 54.4, 54.7, 54.8, 54.9)
- **Stem (55s)**: 55 | 0, 1, 6 (i.e., 55.0, 55.1, 55.6)

### a. How many cars were sampled?
Each leaf represents a single car, so we count the number of leaves:

- 50: 1 car (50.3)
- 51: 1 car (51.4)
- 52: 3 cars (52.0, 52.1, 52.4)
- 53: 5 cars (53.2, 53.4, 53.4, 53.7, 53.8)
- 54: 7 cars (54.1, 54.1, 54.4, 54.4, 54.7, 54.8, 54.9)
- 55: 3 cars (55.0, 55.1, 55.6)

So, the total number of cars sampled is:
\[ 1 + 1 + 3 + 5 + 7 + 3 = 20 \]
Thus, **20 cars** were sampled.

### b. How many cars traveled through the intersection at 54.1 km/h?
Looking at the stem "54" and the leaves, we see two occurrences of "1", which represent two cars traveling at **54.1 km/h**. 
Thus, **2 cars** traveled at 54.1 km/h.

### c. What is the highest speed (km/h) recorded?
The highest stem is "55" and the highest leaf in that row is "6", meaning the highest speed recorded is **55.6 km/h**.

### d. Is the distribution skewed positively or negatively?
- A positively skewed distribution (right-skewed) has more lower values and a long tail on the right (higher values).
- A negatively skewed distribution (left-skewed) has more higher values and a long tail on the left (lower values).

In this case, the majority of data is concentrated around 53 and 54 km/h, with fewer observations at the lower end (50, 51 km/h) and at the upper end (55 km/h). The data seems slightly **positively skewed**, with a tail on the higher end (above 54 km/h).

### Summary of Answers:
a. **20 cars** were sampled.
b. **2 cars** traveled at 54.1 km/h.
c. The highest speed recorded was **55.6 km/h**.
d. The distribution is **positively skewed**.

Would you like more details on any of these points?

Here are some additional related questions:
1. What is the median speed of the cars sampled?
2. What is the mode of the car speeds?
3. How would you calculate the range of the speeds?
4. What would the mean speed be, approximately?
5. How could you identify any outliers in this data?

**Tip**: In a stem-and-leaf plot, the "stem" represents the leading digits, and the "leaf" represents the final digit of the data values.

The following stem-and-leaf plot is constructed using data collected from the speed (km/h) of cars passing through an intersection. Data values were rounded to one decimal place. Stem Leaf 50 3 51 4 52 0 1 4 53 2 4 4 7 8 54 1 1 4 4 7 8 9 55 0 1 6 Key: 50 | 3 = 50.3 km/h a. How many cars were sampled? b. How many cars traveled through the intersection at 54.1 km/h? c. What is the highest speed (km/h) recorded? d. Is the distribution skewed positively or negatively?

Explore how to interpret a stem-and-leaf plot with car speed data. This problem covers essential statistics concepts such as sample size, mode, highest value, and data skewness. Learn how many cars were sampled, the highest recorded speed, and whether the data is positively skewed. Suitable for students in Grades 6-9.

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