Question

I NEED A CORRET ANSWER

One-third of the students in class scored 90% or better on a test. Two-fifths of the students scored 80% - 89% on the test. The rest of the students scored below 80% on the test. What fraction of the students scored below 80% on the test?

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(1 point)
Enter your response a FRACTION to receive credit for this problem.


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Answer 1

I need a correct one

Answer 2

Enter your response a FRACTION to receive credit for this problem.

Answer 3

is that CORRECT ?!

Answer 4

To find the fraction of students who scored below 80%, we can start by determining the fractions of students who scored 90% or better and those who scored between 80% and 89%.

1. **Fraction of students who scored 90% or better:**
This fraction is given as \( \frac{1}{3} \).

2. **Fraction of students who scored between 80% and 89%:**
This fraction is given as \( \frac{2}{5} \).

3. **Adding these fractions together:**
To find the total fraction of students who scored either 90% or better or 80%-89%, we add the two fractions. To do this, we first need a common denominator. The least common multiple of 3 and 5 is 15.

- Convert \( \frac{1}{3} \) to have a denominator of 15:
\[
\frac{1}{3} = \frac{5}{15}
\]

- Convert \( \frac{2}{5} \) to have a denominator of 15:
\[
\frac{2}{5} = \frac{6}{15}
\]

4. **Adding the two fractions:**
\[
\frac{5}{15} + \frac{6}{15} = \frac{11}{15}
\]

5. **Finding the fraction of students who scored below 80%:**
The total fraction of students is 1 (or \( \frac{15}{15} \)). Therefore, the fraction of students who scored below 80% is:
\[
1 - \frac{11}{15} = \frac{15}{15} - \frac{11}{15} = \frac{4}{15}
\]

Thus, the fraction of students who scored below 80% on the test is:
\[
\frac{4}{15}
\]

Answer 5

Let's go through the calculations step by step again to ensure the accuracy of the answer.

1. **Fraction of students who scored 90% or better:**
\(\frac{1}{3}\)

2. **Fraction of students who scored between 80% and 89%:**
\(\frac{2}{5}\)

3. **Finding a common denominator to add the fractions:**
- The least common multiple (LCM) of 3 and 5 is 15.

- Convert \(\frac{1}{3}\) to have a denominator of 15:
\[
\frac{1}{3} = \frac{5}{15}
\]

- Convert \(\frac{2}{5}\) to have a denominator of 15:
\[
\frac{2}{5} = \frac{6}{15}
\]

4. **Adding the two fractions:**
\[
\frac{5}{15} + \frac{6}{15} = \frac{11}{15}
\]

5. **Finding the fraction of students who scored below 80%:**
The total fraction of students who scored either 90% or better or 80%-89% is \(\frac{11}{15}\). Therefore, the fraction of students who scored below 80% is:
\[
1 - \frac{11}{15} = \frac{15}{15} - \frac{11}{15} = \frac{4}{15}
\]

**Final Answer:** The fraction of students who scored below 80% on the test is \(\frac{4}{15}\).

Answer 6

The fraction of students who scored below 80% on the test is:

\[
\frac{4}{15}
\]

Please enter **4/15** as your response.

Answer 7

Yes, the answer is correct. Let's confirm the calculation step-by-step one more time:

**1. Fractions for the scores:**
- One-third of the students scored 90% or better: \( \frac{1}{3} \)
- Two-fifths of the students scored 80% to 89%: \( \frac{2}{5} \)

**2. Finding a common denominator:**
- The common denominator of 3 and 5 is 15.
- Convert \( \frac{1}{3} \) to \( \frac{5}{15} \).
- Convert \( \frac{2}{5} \) to \( \frac{6}{15} \).

**3. Add the fractions:**
\[
\frac{5}{15} + \frac{6}{15} = \frac{11}{15}
\]

**4. Calculate the fraction of students scoring below 80%:**
- Total students = 1 (or \( \frac{15}{15} \)).
- Students scoring below 80%:
\[
1 - \frac{11}{15} = \frac{15}{15} - \frac{11}{15} = \frac{4}{15}
\]

Thus, the fraction of students who scored below 80% on the test is indeed \( \frac{4}{15} \).

So, your answer of **4/15** is correct.