We are Aggelos, Anastasis and George!!!!

This is our first challenge and it is addressed to group 3_Spain.

ENIGMATH από Anastasis Daskalakis

Enjoy!!

This is our second challenge and it is addressed to group 4_Spain.

ENIGMATH από Anastasis Daskalakis

This is the solution for the 2nd riddle:

If x is Kostas' age then his brother's age is x-10 
so 5 years ago his age was:

χ-5 = 2( χ-10-5)
χ-5 = 2(χ-15)
χ-5 = 2χ -30
χ=25

This is the solution to the first challenge:

From the data it follows that Alice, Enrique, 
Kostas and Catherine cannot be in first place.
But since Alice was ranked in an odd position,
Helen would be ranked in an even position and therefore
she was not first either.
So Giorgos took the first place and therefore Kostas
took the third place.
So Alice got the fifth place, after being ranked in an odd place.
Since Esther was neither first nor last,
she took second place and last was Catherine.
The final ranking is:

1. George
2. Enrique
3. Kostas
4. Esther
5. Alice
6. Catherine