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Primary 6 Problem Sums/Word Problems - Try FREE

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(Single Attempt)

Question

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A series of diagrams of a shaded and unshaded small triangles is shown below.

The shaded triangles are those which have at least one side on the edge of the big triangle.

All of the other small triangles are unshaded.

(a) Find the number of unshaded triangles in Diagram 20

(b) Find the total number of triangles in Diagram 32

(c) Find the number of shaded triangles in Diagram 40

(d) Find the number of unshaded triangles in Diagram 50

(e) Find the total number of triangles in Diagram 80

 

 

Notes to students:

  1. If the question above has parts, (e.g. (a) and (b)), given that the answer for part (a) is 10 and the answer for part (b) is 12, give your answer as:10,12

 

The correct answer is : 381,1089,120,2451,6561
(a)____(b)____(c)____(d)____(e)_____