Good Riddles

Question: Mary Jane is stranded on a deserted island in the middle of a huge and deep lake. She cannot swim and all she has is two strings that are each one foot long. All of the boats that she would be able to use are docked at the shore 4 miles away from her. 2 hours later, she is on the shore of the lake. How did she get across the lake?

Question: No matter how hard you try,
I can open what you can't.
If it wasn't for me,
on your front porch you would stand.

What am I?

Question: A smart landscaper is given the task of placing 4 trees so that they are all the same distant away from each other.

How does he do this?

Question: I was taking a plane to China and almost missed my flight. On my way to the terminal there were 7 other girls walking in the opposite direction. Each of these girls had 8 purses and each purse had 2 dogs.

How many in all were on the plane?

Question: Fill in the blank: Ebere is the Michael's daughter. So Michael is the ____ of Ebere's father?