On a 5 1/2 hour trip, Liz drove 2/3 of the time. For how many hours did Liz drive

330 minutes

Make it easy by converting the hours into minutes, and then divide:

1 hour = 60 minutes

2 hours = 120 minutes

3 hours = 180 minutes

4 hours = 240 minutes

5 hours = 300 minutes

+

1/2 hour = 30 minutes

330 minutes

Now divide by 2/3 or divide by 3 and multiply by two:

330 / 3 = 110 • 2 = 220

She drove for 220 minutes, and converted, he drove for 3 hours and 40 minutes.

b.an increase in a causes b to decrease