Final answer:
Sam can type at a constant of proportionality of 46 words per minute, as calculated by dividing the total number of words typed (368) by the total minutes taken (8).
Step-by-step explanation:
The question asks us to find the constant of proportionality that relates the number of words typed to the number of minutes it took to type those words. To find the constant of proportionality, we divide the total number of words by the total number of minutes:
y = 368 words
x = 8 minutes
Constant of proportionality (k) = y / x = 368 / 8 = 46 words per minute.
Therefore, the constant of proportionality is 46 words per minute, which means the correct answer is A. 46.