I NEED A CORRET ANSWER

Question

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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Answer 1

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 2

I need a correct one

Answer 3

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 4

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

Answer 5

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

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

Please enter 4/15 as your response.

Answer 6

is that CORRECT ?!

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.