6) A boys quarterly test grades were 67, 74, 86, and 89. What was the average of his test grades?
a.
5 1/8
b.
10
c.
none of these
d.
20%
e.
$.45
f.
16 3/4%
g.
$2,200
h.
1,600 miles
i.
79
j.
-9