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Winter Math counting and probability IA

 
 
WangChristina的头像
Winter Math counting and probability IA
WangChristina - 2021年01月28日 Thursday 14:57
 

I don't understand question 7.21 or 7.22

 
LensmireJohn的头像
Re: Winter Math counting and probability IA
LensmireJohn - 2021年01月29日 Friday 15:03
 

Hi Christina,

Was your other forum post asking about 7.21 from Counting and Probability as well? It does involve Geometry.

For 7.21, you want to try to find how many diagonals an equilateral triangle, a square, a regular pentagon, and a regular hexagon have. For example, the regular octagon (pictured below) has $5+5+4+3+2+1 = 20$ diagonals (the dotted lines).


As a hint for 7.22, it also involved geometry! Think about other things you know about triangles, quadrilaterals, pentagons, hexagons, etc.

Hope these hints help!