What is the length of the longest object that can be placed in a box 15 cm long, 20 cm wide, and 60 cm high

To get the length of the longest object that can be placed inside a 15-by-20-by-60 cm box. We need to use the formula:

d² = (height)² + c² or
d² = 60² + c²

In order to find the value of c, we will use the Pythagorean Theorem: c² = a² + b²

c² = a² + b²

c² = 20² + 15²

c² = 400 + 225

c² = 625

Going back to the first right triangle:

d² = 60² + c²

d² = 60² + 625

d² = 3600 + 625

d² = 4225

Therefore, d = 65 cm (length of the longest object)

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