On my exam, I will be expected to calculate a simple lower of cost or

On my exam, I will be expected to calculate a simple lower of cost or market adjustment
My professor explained it to me like this
If your cost is higher than what you can get out of it, you adjust it down
If your probable future economic benefit is higher, no journal entry required
I am pretty sure I get this idea conceptually, but could you write me a question that would force me to apply this concept? So write the question, then explain how you adjusted it.