Answer:
She spend 1/18 hour on each type of stretch.
Explanation:
Elin's problem is to divide the total hours 1/3 into 6 type of stretches, equally. And that's what we have to do, divide, that's it. The equation would be:

Because, we want to find the time per stretch that must sum 1/3 of an hour. Now, we solve for
:

Therefore, she spend 1/18 hour on each type of stretch.