The perimeter of a triangle is 160 cm. If two of the sides are 40 cm and 50 cm, calculate the length of the third side?
How many sides are there? ** To get the perimeter, you add all the sides o the triangles, so the first two sides add up to 40+50 = <<40+50=90>>90 cm.
How long is the remaining side? ** If the perimeter of the triangle is 160, the remaining side is 160-90 = <<160-90=70>>70 cm.
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