Kyra typed 140 words in 5 minuets. Then, she typed 196 words in 7 minutes. Was her rate of words per minute constant? If so, what is the constant of proportionality?

Hello lamdravenox! There are a few ways to tell if the rate of words per minute are constant but we can divide 140/5 and 196/7 to tell if the rate of words per minute are constant.

First divide 140 / 5 = 28 words per min

Second divide 196 / 7 = 28 words per min

So we can see the rate of words per minute is constants and her rate is at 28 words per min so the constant of proportionality is 28 words per minute.