AMC 8 Daily Practice - Triangle Properties

Complete problem set with solutions and individual problem pages

Problem 8 Easy

What is the largest whole number smaller than the perimeter of any triangle with a side of length 4 and a side of length 91?

  • A.

    182

  • B.

    184

  • C.

    186

  • D.

    188

  • E.

    190

Answer:A

From the Triangle Inequality Theorem, we know that for the third side s of the triangle, the following must hold: s < 4 + 91 = 95 and s > 91 - 4 = 87.

Let P be the perimeter of the triangle, so P = 4 + 91 + s.

Adding 4 + 91 to all parts of the inequality for s, we get: 87 + 4 + 91 < P < 95 + 4 + 91

182 < P < 190

Thus, the largest whole number smaller than the perimeter of any such triangle is 182.