GRE
$$\frac{n!}{(\frac{n}{2})!}$$
2($$\frac{n}{2}$$)!
The number of ordered pairs (x, y) in S such that x=y
16
$$(x-y)^{2}$$
3
a+b
10
y
8
The percent of the employees at Company X yesterday who did not leave for the day before 6 P.M
20%
RS
TU
The list price of the belt
The list price of the scarf
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