Answer
a. $1/3$
b. $1/3$
c. $1/4$
d. (c)
Work Step by Step
Total outcomes $6\times6=36$
a. A sum of 8, 9, or 10
There are 15 outcomes (26,35,36,44,45,46,53,54,55,62,63,64),
$p=\frac{12}{36}=\frac{1}{3}$
b. Doubles or a sum of 7
12 outcomes (11,16,22,25,33,34,44,43,55,52,66,61),
$p=\frac{12}{36}=\frac{1}{3}$
c. A sum greater than 9 or less than 4
9 outcomes (11,12,21,46,55,56,64,65,66),
$p=\frac{9}{36}=\frac{1}{4}$
d) The smallest probability is (c): a sum greater than 9 or less than 4.
