Question

In the DBE 122 class, there are 350 possible points. These points come from 5 homework sets that are worth 10 points each and 3 exams that are worth 100 points each. A student had received homework scores of 7,8,7,5, and 8 and the first two exam scores are 81 and 80. Assuming that grades are assigned according to the standard scale, where if the grade percentage is 0.9 or higher the student will get an A and if the grade percentage is between 0.8 and 0.9 the student will get a B, and there are no weights assigned to any of the grades. Is it possible for the student to receive an A in the class? What is the minimum score on the third exam that will give an A? What about a B?​

Answer 1

Answer:

$\large \boxed{\textbf{1. No; 2. 119; 3. 84}}$

Step-by-step explanation:

Score = Σ(tests) + Σ(exams) = (7 + 8 + 7 + 5) + (81 + 80 + x) = 35 + 161  + x = 196 + x

To receive an A, the student must score at least 0.9 × 350 = 315 points

To receive a B, the student must score at least   0.8 × 350 = 280 points.

1. Can the student receive an A?

$\begin{array}{rcl}196 + x & \geq & 315\\x & \geq & 315 - 196\\& \geq & \mathbf{119}\\\end{array}\\\text{ \large \boxed{\textbf{No.}} The student cannot make an A on the test.}$

2. Minimum score for an A

$\text{The minimum score for an A is \large \boxed{\mathbf{119}} }$

3. Minimum score for a B

$\begin{array}{rcl}196 + x & \geq & 280\\x & \geq & 280 - 196\\& \geq & \mathbf{84}\\\end{array}\\\text{The minimum score for a B is \large \boxed{\mathbf{84}} }}$