Question

Lynn has 4 grades in science class. Each grade is worth 100 points. Lynn has an 85% average. If Lynn made 100% on each of the first 3 grades, what did she earn on her 4th grade?

a) 60
b) 70
c) 80
d) 90

Answer 1

Lynn earned a grade of 40 on her fourth grade.

Step-by-step explanation:

To find out what Lynn earned on her fourth grade, we need to calculate the average of all four grades. We know that her average is 85%, and she obtained 100% on each of the first three grades. Let's set up an equation:

(100 + 100 + 100 + x) / 4 = 85

Multiplying both sides of the equation by 4 gives:

300 + x = 340

Subtracting 300 from both sides gives:

x = 40

Therefore, Lynn earned a grade of 40 on her fourth grade.