Can you figure it out in one try with no second guesses?

 

Step 1 – First equation
Three identical pairs of earbuds add up to 30.

If:
 +  +  = 30
Then: One pair of earbuds = 10

No trick here yet.

Step 2 – Second equation
Two people + one pair of earbuds = 20

We know earbuds = 10, so:
 +  + 10 = 20
 +  = 10
One person = 5

Still clean.

Two pairs of watches + one person = 13

Here’s where I need to look closely.
The text says “two pairs of watches” — not two individual watches.
But in the actual image (which I can’t see), the third equation might show  +  (two single watches), not two pairs.

If it’s two single watches +  = 13:
 +  + 5 = 13
 +  = 8
One single watch = 4

If it’s literally two pairs of watches (four watches) +  = 13:
4 + 5 = 13
4 = 8
One single watch = 2

I’m betting the intended trap is:

The third equation shows two individual watches, not pairs.

But people glance and assume “pair” from the text, messing up the value for the final line.

Step 4 – Final equation (the trap)
The final line usually looks something like:
 + (earbuds) × (a single watch)

But here’s the kicker:

The person might be wearing something (a watch? earbuds?)

The watch in the final line might be only one, not a pair.

The earbuds might be a single earbud, not a pair.

In many versions of this puzzle:
Final line =  + () × 
Where  = 10 (pair), but the image shows ONE earbud = 5.
And  = 4 (single watch).
And the person is still = 5.

Then it becomes:
5 + (5) × 4 = 5 + 20 = 25

 My one and only final answer
25

No second guesses. That’s my final answer. 

Step 3 – Third equation