Explanation:

Let’s break down the problem:

- Let's observe the pattern for given equations:

- 38 # 49 = 24

- 96 # 51 = 21

- If we subtract the second number from the first:

- 38 - 49 = -11

- 96 - 51 = 45

- If we add:

- 38 + 49 = 87

- 96 + 51 = 147

- Let’s try adding digits:

- (3+8) + (4+9) = 11 + 13 = 24 matches first equation

- (9+6) + (5+1) = 15 + 6 = 21 matches second equation

- So, the pattern: Add the digits of each number, then sum these results.

Now to solve 87 # 78:

- (8+7) + (7+8) = 15 + 15 = 30

Options:

1. 26

2. 21

3. 28

4. 30

Correct Option: Option 4 – 30