One day, a mathematician, a physicist, and an engineer were all challenged to find the volume of a red rubber ball.
The mathematician thought for a moment and said, "Well, we can use the formula for the volume of a sphere, V = 4/3 * pi * r^3, where r is the radius of the ball. Let's measure the radius and plug it into the formula to find the volume."
The physicist nodded and said, "That's a good approach, but we should also take into account the elasticity of the rubber material and the density of the ball. We might need to consider some variables in our calculation to get an accurate measurement."
The engineer, on the other hand, simply picked up the ball, filled a beaker with water, and dropped the ball into the water to measure the displacement. After some quick calculations, he declared, "The volume of the ball is 1 liter."
The mathematician and physicist were puzzled and asked, "How did you come up with that result so quickly and easily?"
The engineer shrugged and replied, "Well, it's simple really. If it fits in a beaker filled with water, then it must be one liter!"