The following frequency distribution analyzes the scores on a math test.

Find the class boundaries of the scores interval 90-99.

| Scores | Number of Students |
|-------------------|--------------------|
| 50-59 | 2 |
| 60-69 | 4 |
| 70-79 | 6 |
| 80-89 | 15 |
| 90-99 | 5 |

A. 90.5, 99.5
B. 89.5, 99.5
C. 89.5, 100.5
D. 89.5, 100.5

The class boundaries for the scores interval 90-99 in a frequency distribution are 89.5 to 99.5, providing a seamless transition between adjacent intervals without gaps.

Explanation:

To find the class boundaries of the scores interval 90-99 for a frequency distribution, we look at the given intervals in the distribution.

Class boundaries are the numbers that separate classes without forming gaps between them. In this case, since the previous class ends at 89 and there are no gaps, the lower boundary for the 90-99 interval starts immediately after, which would be 89.5. The upper class boundary is the next possible value before the next interval starts, which would be 99.5 if the next class would start at 100.

Hence, the correct class boundaries for the interval 90-99 are 89.5 to 99.5 (Option B).