11 Plus Exams Forum

Hi. Can someone explain this to me.

Nina has some sticks of different lengths. She can lay the sticks end to end to make triangles.
She chooses sticks with lengths:
2cm, 3cm, 5cm, 6cm, 8cm.

Which of these sets of three sticks can Nina use to make a triangle.

A 2cm, 3cm, 5cm
B 2cm, 3cm, 6cm
C 2cm, 3cm, 8cm
D 3cm, 5cm, 6cm
E 3cm, 5cm, 8cm


The Answer given is D but I'm not sure how they arrived at this.

** They had a picture of a scalene triangle.


Thanks.

If you have a triangle then think about the lengths of the two shorter sides compared to the longest.

e.g. 2, 3, 5 can't be a triangle because 2 + 3 = 5 and the two sticks are the same length as the third

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Sorry, hard to draw - try with some practical equipment so you can see the limitations on lengths of sides.

Triangle has 3 sides.
The length of the longest side must always be less than the total length of the other 2 sides.
Try drawing a triangle with sides 2,3 and 5. You will only be able to draw a line.

Thanks a lot to everyone who responded. Really helped a lot.
Much appreciated!