Question

a student answers 90% of the questions on a math exam correctly. if he answers 18 questions correctly, there are \\(\square\\) questions on the exam. (type a whole number.)

Explanation:

Step1: Define the problem

Let \( x \) be the total number of questions on the exam. We know that 90% of \( x \) is equal to 18 (the number of correct answers). So we can write the equation \( 0.9x = 18 \).

Step2: Solve for \( x \)

To find \( x \), we divide both sides of the equation by 0.9. So \( x=\frac{18}{0.9} \). Calculating this, \( \frac{18}{0.9} = 20 \).

Answer:

20