This is a nice solution, but points up a
problem we all have trying to communicate about math in writing. What
does the table mean? Here's what I think:
The first line means that when Dwight is 9,
Chelsea will be 1 (person year), therefore 6 dog years. (The C stands
for Chelsea). I think the students are tring to see when the clue
"Chelsea is twice as many dog years right now as Dwight is in
person-years" becomes true. They must be older than this, because
Chelsea is still too young.
The second is the next guess, and it's a
good one! Three years later, Dwight will be twelve and Chelsea will
be 4 (in person years) which is 24 dog years. And that's twice
Dwight's age. Whew!
The third line solves for Sadie: her
person-years must be 8 (1/3 of 24, last clue), so she's 48 dog years
The question is, how could we make that
table so it would be clearer without having to write all the
sentences I did?