Question

A triangle has two sides of length 16 and 21. What is the smallest possible whole-number length for the third side?

Answer 1

By the triangle inequality, the third side c must satisfy c > |21 − 16| = 5 and c < 21 + 16 = 37. The smallest whole-number length is 6 (which indeed gives 6 + 16 > 21, etc.).