Answer
12,565,671,261
Work Step by Step
Let $x_{i}$ be the questions in the test
then $x_{i}\geq$5
and $x_{1}+x_{2}+...x_{10}$=100
let us define $X_{i}$=$x_{i}$-5
so $X_{i}\geq$0
and $X_{1}+X_{2}+...X_{10}$=100-50 = 50
select 50 indistinguishable objects from 10 distinguishable boxes
n=10
r=50
Repetition is allowed,
$C$(59,50) = 12,565,671,261
