Simple Math

It's just simple order of operations.

Multiplication and Division take precedence over Addition and Subtraction, so they're evaluated first:

$1\quad +\quad 1\quad +\quad 1\quad +\quad 1\quad \times \quad 0\quad =\quad ?\\ 1\quad +\quad 1\quad +\quad 1\quad +\quad \quad \quad 0\quad \quad \quad =\quad ?\\ \quad \quad 1\quad +\quad 1\quad +\quad 1\quad =\quad \boxed { \quad 3\quad }$

$1+1+1+1 \times 0$ =

$1+1+1+0$

= $3$

$1 + 1 + 1 + 1 × 0 = 1+1+1 = \color{#69047E}{\boxed{3}}$ .

my solution is that... $1+1+1+1*0$ $\Rightarrow$ $1+1+1+0=3$

You said 95% will answer incorrectly but only 22% answered incorrectly.