Educational diagram illustrating cell structure and organelles with handwritten annotations.

It looks like you've uploaded an image containing a math problem, but the text is not fully legible or clear. However, based on the visible parts of your image, it seems to be a mathematical logic or set theory problem involving sets, subsets, and possibly Venn diagrams, with a focus on understanding relationships between sets.

Let me try to reconstruct and solve the problem based on what's visible:

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Problem Summary (Based on Visible Text):

We are given a scenario involving two sets:

- Let A be the set of all students who have a computer at home.
- Let B be the set of all students who have a smartphone at home.

We're told:
- Some students have both a computer and a smartphone.
- The total number of students in the class is 30.
- 18 students have a computer.
- 20 students have a smartphone.
- We are to find how many students have both a computer and a smartphone.

This is a classic principle of inclusion-exclusion problem.

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Step-by-Step Solution:

Let:
- $ |A| = 18 $ → number of students with a computer
- $ |B| = 20 $ → number of students with a smartphone
- $ |A \cup B| = 30 $ → total number of students (assuming every student has at least one device)
- $ |A \cap B| = ? $ → number of students with both

Using the inclusion-exclusion principle:

$$
|A \cup B| = |A| + |B| - |A \cap B|
$$

Substitute known values:

$$
30 = 18 + 20 - |A \cap B|
$$

$$
30 = 38 - |A \cap B|
$$

$$
|A \cap B| = 38 - 30 = 8
$$

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✔ Final Answer:

$$
\boxed{8}
$$

So, 8 students have both a computer and a smartphone.

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Explanation:

- If we simply added 18 + 20 = 38, that would count students with both devices twice.
- Since there are only 30 students total, the overlap (both) must be $ 38 - 30 = 8 $.
- This means 8 students are counted in both groups.

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If your image contains a different problem (e.g., about logical statements, Venn diagrams, or something else), please clarify or re-upload a clearer version so I can give a more accurate solution.

But based on what’s visible, this is the most likely interpretation.