Directions: What approximate value should come in place of the question mark (?) in the following question?

${26.19}^2+13.91=?\times (49.97\%\text{of}60.12)$

The correct answer is 23.

We are given the following approximation equation:

${26.19}^2+13.91=?\times (49.97\%\text{of}60.12)$

Step 1: Approximate each decimal number to its nearest integer.

• $26.19\approx 26$

• $13.91\approx 14$

• $49.97\%\approx 50\%$

• $60.12\approx 60$

Step 2: Simplify the left-hand side (LHS) of the equation.

Calculate the square of 26:

${26}^2=676$

Add 14 to 676:

$\text{LHS}=676+14=690$

Step 3: Simplify the expression inside the bracket on the right-hand side (RHS).

Calculate 50% of 60:

$50\%\text{of}60=\frac{50}{100}\times 60=30$

Step 4: Substitute the simplified values back into the equation to solve for the unknown value (?).

$690=?\times 30$

$?=\frac{690}{30}$

$?=23$

Hence, the approximate value that should come in place of the question mark is 23.