If + means − , − means × , × means ÷ , ÷ means +, what will come in place of the question mark (?) in the given equation?
180 × 60 – 30 ÷ 30 + 20 = ?

The correct answer is 100.

Step-by-step explanation:

We are given the following operator substitutions:

• '+' means '−'
• '−' means '×'
• '×' means '÷'
• '÷' means '+'

The given equation is:

$180\times 60-30÷30+20=?$

Replacing the original operators with their substituted values according to the instructions:

$180÷60\times 30+30-20=?$

Now, evaluate the expression step-by-step following the standard BODMAS / PEMDAS order of operations (Division, Multiplication, Addition, Subtraction):

Step 1: Perform Division

$180÷60=3$

Substituting this result back into the equation:

$3\times 30+30-20$

Step 2: Perform Multiplication

$3\times 30=90$

Substituting this result back into the equation:

$90+30-20$

Step 3: Perform Addition

$90+30=120$

Substituting this result back into the equation:

$120-20$

Step 4: Perform Subtraction

$120-20=100$

Thus, the value that replaces the question mark (?) is 100.