Sunday, January 21, 2007

Proportion Practice

Proportion Practice

Here are some links that will help you practice proportional pr0blem solving.


  1. Fraction Four Like connect 4 but using fractions.
  2. Proportion Quiz Practice multiple choice problems. This is a good review.
  3. Percent Calculator Can you figure out 2 different ways to show a fraction as a percent?
  4. Brain Pop Movie and Quiz on proportion. Watch the movie, learn a little algebra and then take a quiz. couldn't get any better than this!!!
Try these questions out. Leave answers as comments.

A.)Make a list of at least 5 friends to invite to a party so that the ratio of boys to girls is 2:1. Explain how you know that the ratio of boys to girls is 2:1.

B.) A newspaper article says that that 15% of the people in Athens eat out every night. There are approximately 50 000 people in Athens and there are about 25 restaurants. Do you think that the newspaper is correct? Explain why or why not and back up your answer using your proportional problem solving skills.

Here is a movie showing you 3 different ways to solve a proportion.





Here is a movie showing you how to solve proportion word problems.





3 comments:

apuya_soldier_ said...

haha. those vids gave me an 8 minute math class. well for the questions..

A.)Make a list of at least 5 friends to invite to a party so that the ratio of boys to girls is 2:1. Explain how you know that the ratio of boys to girls is 2:1.

ok so...

boys:girls..2:1

..right now thats kinda hard to figure out, even if you put it to fractions.. 2/3 = /5? that works about to..3.333/5. you cant really have 3.333 boys in a group, unless the group is all boys. haha. but really. so first ill simplify it (or is it complicate?) to 4/6.

so then thats..

boys:girls 4/2. so thats 4 guys out of a total of 6 people.
and the ratio is 2:1 because 4/2 = 2/1.


so since it does ask for a list of friends....

-spongebob
-patrick
-squidward
-chuck norris
-sandy
-pearl (ehh why not.)

B.) A newspaper article says that that 15% of the people in Athens eat out every night. There are approximately 50 000 people in Athens and there are about 25 restaurants. Do you think that the newspaper is correct? Explain why or why not and back up your answer using your proportional problem solving skills.

*looks at the second video*

ok so..
15% of 50000 is 7500.
so for that 15% there are 25 restaurants.
7500 / 25 = 300
so..
people/restaurants = 7500/25 = 300/1

so thats 300 people for each restuarant at night. im not sure if that would be correct. it depends on if its fast food or extremely fancy..or how big...or how good the food is...id say it isnt because 300 can be too much for each restaurant.

-apuya

ardiasarao said...

A.)Make a list of at least 5 friends to invite to a party so that the ratio of boys to girls is 2:1. Explain how you know that the ratio of boys to girls is 2:1.

okay .. 2:1 is boys:girls

fraction is 2/3 because 2 + 1 = 3 .
its said to have AT LEAST 5 people .. so i can use more =) .. ahaha so lets make it 15 people.
because 3 X 5 = 15 so 10/15 is equal to 2/3 because both numerator and denominator a divisible by 5.
so 10/15 is simplified to 2/3 and the ratio is 2:1

my friends :
-guy
-guy
-girl
repeat that 5 more times .. because for one girl there will be 2 guys =)

B.) A newspaper article says that that 15% of the people in Athens eat out every night. There are approximately 50 000 people in Athens and there are about 25 restaurants. Do you think that the newspaper is correct? Explain why or why not and back up your answer using your proportional problem solving skills.

okay so .. there are 50 000 people .. since michael used one way .. i use another way .. but its longer xp

50 000 is 100%
50 000 divided by 100 = 500 or 1%
500 x 15 = 7500
1% x 15 = 15%

7500 people divided by 25 restaurants ..

7500 divided by 25 = 300
so 300 people for each restaurant .. WOW that must be one big restaurant xp

--ardiasarao =)

tears_77 said...

A.)Make a list of at least 5 friends to invite to a party so that the ratio of boys to girls is 2:1. Explain how you know that the ratio of boys to girls is 2:1.

The questions said "Make a list of at least 5 friends", so it means I can invite more than 5 firends. The ratio of boys to girls is 2:1 so for my friend list, I'm going to invite 6 people. 4 guys and 2 girls. Even though the ratio of boys to girls in my friend list is 4:2 it is still 2:1. I just doubled it. 2x2 = 4 and 1x2 = 2.

How I got the answer:
Well I just pretended the ratio 2:1 is a fraction which is 2/1. Then I asked myself what is a equivalent fraction to 2/1 and I got 4/2. When you simplify 4/2 you get 2/1.

How to Simplify:
Numerator divided by a number
Denominator divided by the same number.

4 divided by 2 = 2
2 divided by 2 = 1

Invitation List:
Ratio of boys to girls = 4:2 or 2:1

1) guy - Shaggy
2) guy - Fred
3) girl- Velma
4) guy - Scooby Doo *
5) guy - Scrappy Doo *
6) girl- Daphne

* Scooby Doo and Scrappy Doo are male dogs so on this question I consider then guys. Okay!!!

B.) A newspaper article says that that 15% of the people in Athens eat out every night. There are approximately 50 000 people in Athens and there are about 25 restaurants. Do you think that the newspaper is correct? Explain why or why not and back up your answer using your proportional problem solving skills.

Total people = 50 000
Percent = 15%
Restaurants = 25

First of all, figure out what is 15% of 50 000.

Decimal of 15% is 0.15

50 000 x 0.15 = 7500

Then divide the 7500 by 25 restaurant to figure out how many people are in one restaurant.

7500 / 25 = 300 people.

I don't think the newspaper was correct because first of all not many people can afford to go to restaurants. Second thing is that 1 restaurant won't be able to occupy and entertain 300 people every night. I don't think they built big restaurants before not like today that one restaurant can handle that many people and even more. We learned about Athens in Social Studies and Athens is small, i don't think 25 huge restaurants are built there.

Proportion way:

n = 1
7500 = 25

To find n:
1 divided by 25 = 0.04
0.04 x 7500 = 300
N =300

Solved proportion:

300 = 1
7500 = 25

So there are 300 people in one restaurant. The newspaper would be correct if a restaurant before can handle 300 people every night and if that much people before can afford to go to restaurants every night.


If you don't understand my explanation look at the second video. That video might help you.