Question

The grades in a mathematics class for the last grading period were: $5$ students earned an A, $4$ earned a B, $3$ earned a C, $3$ earned a D, and $5$ earned an F. If A, B, C, and D are satisfactory grades, what fraction of the grades are satisfactory?

$\dfrac{1}{2}$

$\dfrac{2}{3}$

$\dfrac{3}{4}$

$\dfrac{4}{5}$

$\dfrac{9}{10}$

Solution:

The satisfactory grades number $5 + 4 + 3 + 3 = 15,$ and the total number of grades is $15 + 5 = 20.$

So the fraction that is satisfactory is $\dfrac{15}{20} = \dfrac{3}{4}.$

Thus, the correct answer is C .

1985 AMC 8 Problem 5

Solution:

Problem 5 in Other Years