You have 10 coins….arrange them in 4 straight lines such that each line contains 4 coins, without picking up the pencil.
Edit: You have to arrange the coins in 4 straight lines such that each line has 4 coins.
In below image start with L1, than L2, L3 and L4 without picking up the pencil in a star shape
arrange the coins as in the picture so that each line L1,L2,L3 & L4 have exactly 4 coins
2 fever and 2 cold tablets puzzle