## Math Brain Teaser: Concentric Shapes or The Unkindest Cut of All, Part 2 of 2

If you missed Part 1, also writ­ten by puz­zle mas­ter Wes Car­roll, you can start there and then come back here to Part 2. Con­cen­tric Shapes: The Unkind­est Cut of All, Part 2 of 2.Difficulty: HARDER Type: MATH (Spatial)Question:Imagine a square with­in a cir­cle with­in a square.The cir­cle just grazes each square at exact­ly four points.Find the ratio of the area of the larg­er square to the smaller.In this puz­zle you are work­ing out many of the same skills as in Part I: spa­tial visu­al­iza­tion (occip­i­tal lobes), mem­o­ry (tem­po­ral lobes), log­ic (frontal lobes), plan­ning (frontal lobes), and hypoth­e­sis gen­er­a­tion (frontal lobes).Click to read the Solu­tion and Explanation.

## Math Brain Teaser: The Unkindest Cut of All, Part 1 of 2

Here is anoth­er math­e­mat­i­cal puz­zle from puz­zle mas­ter Wes Car­roll … The Unkind­est Cut Of All, Part 1 of 2.Difficulty: HARD.Type: MATH (Spatial).Question:The area of a square is equal to the square of the length of one side.So, for exam­ple, a square with side length 3 has area (3^2), or 9. What is the area of a square whose diag­o­nal is length 5?

## Brain Teaser: Dr. Nasty’s Giant Cube

Dr. Nasty’s Giant Cube. Dif­fi­cul­ty: HARDER. Type: HYBRID (Logic/Spatial). The dia­bol­i­cal Dr. Nasty has turned his Growth Ray on a per­fect cube that used to mea­sure one foot on a side. The new larg­er cube has twice the sur­face area of the orig­i­nal. Find the vol­ume of the larg­er cube.

## Stress Management Test

A close­ly mon­i­tored, sci­en­tif­ic study revealed that, in spite of the fact that the dol­phins are iden­ti­cal, a per­son under stress would find dif­fer­ences in the two dol­phins.… Look at the pho­to­graph, and if you find more than one or two dif­fer­ences, you may want to take a vacation.