Solving the Algebraic Equation

We are asked to find the value that should replace the question mark (?) in the given equation:

$$15 \times ? + 26 \times 4 = 284$$

Let's represent the question mark (?) with a variable, say x. The equation then becomes:

$$15x + 26 \times 4 = 284$$

Step-by-Step Calculation

Follow these steps to find the value of x:

• Step 1: Calculate the product of 26 and 4.

  $$26 \times 4 = 104$$

• Step 2: Substitute the result back into the equation.

  The equation now looks like this:

  $$15x + 104 = 284$$

• Step 3: Isolate the term containing x.

  To do this, subtract 104 from both sides of the equation:

  $$15x = 284 - 104$$

  $$15x = 180$$

• Step 4: Solve for x.

  Divide both sides of the equation by 15:

  $$x = \frac{180}{15}$$

  $$x = 12$$

So, the value that should come in place of the question mark (?) is 12.

Verification

We can check our answer by plugging 12 back into the original equation:

$$15 \times 12 + 26 \times 4$$

$$180 + 104$$

$$284$$

This matches the right side of the original equation, confirming our answer is correct.