Step by step
The question
Question: 2/3 wall in 1/2 hour: how much is that per hour?
A unit rate says how much for 1 hour.
Per hour means: divide by the hours.
1 Write the rate
Walls divided by hours: 2/3 ÷ 1/2.
Careful!
Not the other way round.
That would be hours per wall.
2 Divide
Dividing by a fraction is the same as times its flip.
Keep the first number.
Change divide to times.
Turn the second fraction upside down.
So 1/2 becomes 2, and divide becomes times.
To multiply fractions, we do top times top, and bottom times bottom.
A whole number is a fraction over 1.
2 times 2 is 4.
3 times 1 is 3.
So the unit rate is 4/3 walls per hour.
3 Check
Let's check: 4/3 walls per hour, for 1/2 hour.
4/3 times 1/2 is 2/3.
That is the walls we started with.
So the answer is right!
Let's look back.
First: write the rate.
Then: divide.
Last: check.