Page 124 - NUMINO Challenge_A1
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03
04 The unfolded piece of paper is as shown below. Count all the different sizes of
triangles you can find.
:8 :4 : 4 16 right triangles
05 You cannot connect three dots on the same line to make a triangle.
1 2 3 There are eight ways in which the numbers of the three
vertices add up to 15.
(1, 5, 9) (1, 6, 8) (2, 6, 7) (2, 5, 8)
4 5 6 (2, 4, 9) (3, 5, 7) (3, 4, 8) (4, 5, 6)
Out of these eight ways, there are four ways in which the
number of the three vertices are on the same line.
7 8 9 (1, 5, 9) (2, 5, 8) (3, 5, 7) (4, 5, 6)
Therefore, there are 8 4 4 ways to draw triangles with their
three vertices adding up to 15.
06 Start by covering the figures with triangles.
Answers will vary.
19Answer Key
04 The unfolded piece of paper is as shown below. Count all the different sizes of
triangles you can find.
:8 :4 : 4 16 right triangles
05 You cannot connect three dots on the same line to make a triangle.
1 2 3 There are eight ways in which the numbers of the three
vertices add up to 15.
(1, 5, 9) (1, 6, 8) (2, 6, 7) (2, 5, 8)
4 5 6 (2, 4, 9) (3, 5, 7) (3, 4, 8) (4, 5, 6)
Out of these eight ways, there are four ways in which the
number of the three vertices are on the same line.
7 8 9 (1, 5, 9) (2, 5, 8) (3, 5, 7) (4, 5, 6)
Therefore, there are 8 4 4 ways to draw triangles with their
three vertices adding up to 15.
06 Start by covering the figures with triangles.
Answers will vary.
19Answer Key
