Sunday, November 6, 2016
Unit Rate Word Problems-Middle School Math-
Middle School Math-Learn how to solve unit rate word problems
Welcome to MooMooMath where we upload a new Math video everyday
In this video I would like to talk about unit rate.
Lets first go over we solve for unit rate
Step 1. Set up a proportion equal to one unit. For example:
If 8 oranges cost 40 cents, what is the cost of 1 orange?
After the proportion is set up cross multiply
Step 3. Solve for x.
Therefore,one orange equals 5 cents
Lets look at some more examples
The first example we have,
If 24 pounds of pumpkin seeds cost $18, how much does 1 pound of pumpkin seed cost?
First lets set up a proportion. 18 dollars equals 24 pounds
I will write dollars out.
I next set the fraction to one and place the same units as the original fraction.
We have 1 pound and our x will be the cost
Notice we have dollars and dollars and pounds and pounds
The next step involves cross multiplying
I end up with 24x = 18
I next isolate the x by dividing by 24
The 24's cancel out and x equals .75
What does this tell us?
Plug the x into the fraction and .75 dollars equals 1 pound.
Therefore, 1 pound of pumpkin seeds equals 1 pound
If 4 shirts at the bargain rack costs 24.24, how much does 1 shirt cost?
Again, set up a proportion.
24.24 is how much 4 shirts cost, and remember with a proportion I need the same units on the top and bottom.
The shirts match up and 1 shirt equals x dollars.
Next I cross multiply
We have 4 x equals 24.24
x will equal to 24.24 divided by 4 which equals 6.06
We can rewrite that as 1 shirt equals 6.06
Finally I have one more.
If a car travels 168 miles in 4 hours, how far does the car travel in one hour?
Place 168 which is how far it travels.
It takes 4 hours.
Set a proportion with miles on top and hours on the botom of the fraction.
Cross multiply to find the unit rate
I have 1 hour here so x will be miles
When I cross multiply I get 4x = 168
Solve for x by dividing both sides by four
x = 42, and I can rewrite that as 1 hour equals 42 miles which tells us is that the car will travel 42 miles in 1 hour.
Hope this helps with unit rate word problems.
MooMooMath uploads a new Math video everyday
At MooMooMath we provide helpful Math and Geometry videos to help you figure out how to solve Math problems or review old Math concepts you may need to refresh. If you’re a Math student or teacher, we'd love to have you subscribe and join us!