I find very good puzzle from YouTube. It was an entrance examination of a University in Japan.
Find the number of rectangles of stairs shown here.
How to calculate the total number of rectangles included in this figure?
You can change the number of stairs by change the Combo-Box to select.
ACCEPTED SOLUTION
Accepted Solutions
Chose 4 stars from 10 stars. First and second stars show the red lines' position and third and fourth stars show the blue lines' position.
These 4 lines make all rectangles you can find from green 7 stairs.
Chose 4 stars from 10 stars. First and second stars show the red lines' position and third and fourth stars show the blue lines' position.
These 4 lines make all rectangles you can find from green 7 stairs.
