In a test,Ben gained 90% by answering 135 questions correctly. how many question did he answer incorrectly?
.9x = 135
solve for x
X questions on test.
0.9x = 135.
X = 150.
150-135 = 15 questions answered incorrectly.
To find out how many questions Ben answered incorrectly, we need to determine the total number of questions.
Let's first find out the total number of questions Ben answered correctly by dividing his score by the percentage:
Total number of questions answered correctly = (Score / Percentage) * 100
Total number of questions answered correctly = (135 / 90) * 100
Total number of questions answered correctly = 150
Now, we can find the number of questions Ben answered incorrectly by subtracting the number of questions answered correctly from the total number of questions:
Number of questions answered incorrectly = Total number of questions - Number of questions answered correctly
Number of questions answered incorrectly = 150 - 135
Number of questions answered incorrectly = 15
Therefore, Ben answered 15 questions incorrectly.
To find out how many questions Ben answered incorrectly, we can first calculate the number of questions he answered correctly. Then, we can subtract this number from the total number of questions to get the number of questions he answered incorrectly.
Given that Ben gained 90% by answering 135 questions correctly, we can set up the following equation:
(Number of questions answered correctly / Total number of questions) * 100 = 90%
Let's solve for the number of questions answered correctly:
(Number of questions answered correctly / Total number of questions) = 90% / 100%
(Number of questions answered correctly / Total number of questions) = 0.9 (decimal form of 90%)
To find the number of questions answered correctly, we can rearrange and solve the equation:
Number of questions answered correctly = (0.9) * Total number of questions
Given that Ben answered 135 questions correctly, we can substitute this value into the equation:
135 = (0.9) * Total number of questions
Now, we can solve for the total number of questions:
Total number of questions = 135 / 0.9
Total number of questions = 150
Since we know the total number of questions is 150, we can now find the number of questions Ben answered incorrectly:
Number of questions answered incorrectly = Total number of questions - Number of questions answered correctly
Number of questions answered incorrectly = 150 - 135
Number of questions answered incorrectly = 15
Therefore, Ben answered 15 questions incorrectly.