Quite often while I'm looking through research articles, I see sentences that start like this one:
The tensile strengths of the composites changed...
I generally change strengths to strength in this case. My thinking is that because "strength" refers to a singular property, rather than multiple different types of tensile strength, I should change it. However, there is a strength associated with each of the composites tested.
Are there any rules that say I shouldn't change the plurality of the subject when it would disagree with the plurality of the object of the prepositional phrase attached to the subject?