This site introduces problems of Sansue, i.e. mathematics which Japanese schoolchildren learn at elementary school. Problems are selected mainly from entrance examinations of famous junior high schools for 6th grade Japanese schoolchildren (12 years old) to take. We found Sansue is not only one of subjects at school but one of Japanese culture. Please enjoy Japanese Sansue culture.
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Math New Drill (Level 2) : Triangles on a circle
There are eight points on the circumference at equal interval. A triangle is made by choosing three points among eight. How many kinds of triangle are made?
Answer Five kinds Solution As 8 = 1 + 1 + 6 = 1 + 2 + 5 = 1 + 3 + 4 = 2 + 2 + 4 = 2 + 3 + 3, there are five kinds as shown below.
