on the test had 50 items gertrude got 34 out of the first 40 correct. if she received a grade of 80% on the test how many of the last 10 did she have correct
80% of 50 questions is 40 questions.
She got 34 right out of the 1st 40, so she had to get 6 more right in the last 10.
To find out how many of the last 10 items Gertrude got correct, we need to determine the overall number of correct answers.
Initially, Gertrude got 34 out of the first 40 correct. This means she had 34/40 = 0.85 or 85% correct on the first 40 items.
Since her overall grade on the test is 80%, we know that Gertrude has 80% correct answers out of the total 50 items.
To calculate the overall number of correct answers, we can set up a proportion:
(34 + x) / 50 = 80 / 100
Cross-multiplying gives us:
100 * (34 + x) = 80 * 50
Simplifying further:
3400 + 100x = 4000
Subtracting 3400 from both sides:
100x = 600
Dividing by 100:
x = 6
Therefore, Gertrude got 6 of the last 10 items correct.
To find out how many of the last 10 questions Gertrude answered correctly, we can first determine her overall score based on the information given.
We know that Gertrude got 34 out of the first 40 questions correct, which means she got 34/40 * 100% = 85% correct on those questions.
Since she received a grade of 80% on the entire test, we can now determine the average score for all the questions.
Let's assume Gertrude answered x questions correctly out of the last 10. The overall score can be calculated as follows:
[(34 correct out of 40) + (x correct out of 10)] / 50 = 80%
To solve for x, we can rearrange the equation:
[(34 + x) / 50] = 0.8
Now we can isolate x by multiplying both sides of the equation by 50:
34 + x = 0.8 * 50
34 + x = 40
Now, solve for x by subtracting 34 from both sides:
x = 40 - 34
x = 6
Therefore, Gertrude had 6 of the last 10 questions correct.