Following arrangement shows 10 coins in three rows of four. Rearrange the same ten coins to make FIVE rows of four. Each line must be straight and must contain exactly four coins.
Put all the coins at the 10 edges of STAR. Then draw four straight cross lines, each line will cover exactly four coins.
"I planted five rows of four Christmas trees each." The man boasted to his boss. The boss looked at him and said, are you saying you planted 20 Christmas trees in one day? No, the man said, I only planted 10 trees. How did he do it?
If we add four times the age of John four years from now to five times his age five years from now we get ten times his current age.
How old will John be two years from now?