use 1,3,5,7,9,11,13,15,17 to make a triangular each side sum of 30 without repeating any of given numbers
3----17----9----1 --15----------13 -----7------11 ---------5
-=-=-=-=-=-=-=-=- 3+17+9+1 = 30 3+15+7+5 = 30 1+13+11+5 = 30
1+15+11+3=30 1+17+7+5=30 3+9+13+5=30
[] + [] + [] = 30
Fill the boxes using one of these numbers 1, 3, 5, 7, 9, 11, 13, 15
You can also repeat the numbers.
In a sequence of eleven real numbers, only two are shown. The product of every 3 successive boxes is 120. Find the sum of all the numbers in the boxes (including the two already open).
_ _ (6) _ _ _ _ _ _ (-4) _
Is it possible to write down 1,2,3..100 in some order (one after an other), such that the sum of any two adjacent numbers is a prime number?