7. Five numbers have the property that, when we add any four of these five numbers, we get the sums 186, 203, 214, 228, and 233. What are these numbers?

The use of a pocket calculator or any manuals is not allowed.
7. Let's denote these numbers as $a, b, c, d$ and $e$.
Then we have:
$a+b+c+d=186$
$a+b+c+e=203$
$a+b+d+e=214$
$a+c+d+e=228$

$b+c+d+e=233$

2 POINTS
By adding all the equations, we get 4 $(a+b+c+d+e)=1064$, ..... 2 POINTS
which means $a+b+c+d+e=266$. ..... 1 POINT
Now we have:
$e=266-186=80$, ..... $1 \text{POINT}$
$d=266-203=63$, ..... $1 \text{POINT}$
$c=266-214=52$, ..... $1 \text{POINT}$
$b=266-228=38$, 1 POINT
$a=266-233=33$.

$1 \text{POINT}$