Question

At a university, the arithmetic mean of the final grades of a group of 5 students in a discipline was 72. Three of these students obtained the following grades: 65, 70 and 80. The two other students got the same grade. Determine the grade of the remaining two students:

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Answer to a math question At a university, the arithmetic mean of the final grades of a group of 5 students in a discipline was 72. Three of these students obtained the following grades: 65, 70 and 80. The two other students got the same grade. Determine the grade of the remaining two students:

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Esmeralda
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102 Answers
1. The arithmetic mean equation is:

\frac{65 + 70 + 80 + 2x}{5} = 72

2. Calculate the sum of the first three grades:

65 + 70 + 80 = 215

3. Substitute into the mean equation:

\frac{215 + 2x}{5} = 72

4. Multiply both sides by 5 to eliminate the denominator:

215 + 2x = 360

5. Solve for \( x \):

2x = 360 - 215

2x = 145

6. Divide both sides by 2 to find \( x \):

x = 72.5

The grade of the remaining two students is 72.5 each.

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