a student answers 90% of the questions on a math exam correctly.if the answers 27 questions correctly.how many questions are on the exam?
its 30
To find out the total number of questions on the math exam, we can use the following steps:
Step 1: Calculate the percentage of questions the student answered correctly.
Percentage = Number of Correctly Answered Questions ÷ Total Number of Questions
Step 2: Substitute the given values into the equation.
90% = 27 ÷ Total Number of Questions
Step 3: Convert the percentage to a decimal by dividing it by 100.
0.90 = 27 ÷ Total Number of Questions
Step 4: Solve the equation for the Total Number of Questions by multiplying both sides of the equation by Total Number of Questions.
0.90 * Total Number of Questions = 27
Step 5: Divide both sides of the equation by 0.90 to isolate the Total Number of Questions.
Total Number of Questions = 27 ÷ 0.90
Step 6: Evaluate the expression to find the Total Number of Questions.
Total Number of Questions ≈ 30
Therefore, there are approximately 30 questions on the math exam.
To find out how many questions are on the exam, we can use a proportion.
Let's say the total number of questions on the exam is represented by 'x'.
Since the student answers 90% of the questions correctly, the number of questions the student answered correctly can be represented as 90% of 'x'.
90% can also be written as a decimal, which is 0.90. Therefore, the number of questions the student answered correctly is 0.90x.
According to the problem, the student answered 27 questions correctly. So, we can set up the following equation:
0.90x = 27
To solve for 'x', divide both sides of the equation by 0.90:
x = 27 / 0.90
Using a calculator, we can find that x is equal to 30.
Hence, there are 30 questions on the exam.
.9x = 27
Solve for x.