plz help with a math problem

[trisharog]

Yikes! I could really use help with this problem:

 

Jenny had 250 more local stamps than Malayasian stamps. After giving 76 local stamps to her friend, she had 1/4 as many Malaysian stamps as local stamps. How many local stamps did Jenny have at first?

 

Thanks

Trisha

[DragonFaerie]

Hm. I'm no math wiz but this is as far as I got with it:

 

x = the number of Malaysian stamps

x + 250 = the number of local stamps

 

But the next part threw me:

 

x + 174 = the number of local stamps after the give away so the equation would be (I think) x + 174 = .25x but I have no idea how to solve that. Then again, I was an English major so I could be WAAAAYYYY off. :tongue_smilie:

 

Oh wait.. maybe it's .25(x + 174) = x? Hmmm....

[Halcyon]

love these bar graph problems LOL

Edited November 1, 2010 by Halcyon

[AngieW in Texas]

This must be a Singapore problem, because I remember helping one of my girls with it at some point.

 

Jenny had 250 more local stamps than Malayasian stamps. After giving 76 local stamps to her friend, she had 1/4 as many Malaysian stamps as local stamps. How many local stamps did Jenny have at first?

 

Draw your rod diagrams like this:

 

starting condition:

[------local-stamps-][------------------------------250----------------------------]

[-Malaysian-stamps-]

 

ending condition (after giving her friend 76 of her local stamps):

[-----local-stamps--][---------------------174-----------------------]

[-Malaysian-stamps-]

 

Now there are 1/4 as many Malaysian stamps as local stamps. That means that 174 has to be equal to 3x the number of Malaysian stamps, so there have to be 174/3 = 58 Malaysian stamps.

[DragonFaerie]

Well, my equation works with plugging in the 58 for x. But I still have no idea how I would have solved it. LOL

[Adrianne in TX]

Angie

Will you teach my kids math to the end of time...watch what you answer...I will see you again :)

Adrianne

[Tattarrattat]

Well, my equation works with plugging in the 58 for x. But I still have no idea how I would have solved it. LOL

 

Using algebra,

 

If x = malaysian stamps,

then x+(250-76)= 4x, x=58, local stamps before = 58+250=308

 

* At the end, local stamps were 4 times of Malaysian stamps, not 1/4 of Malaysian stamps.

 

Or if you choose to use x= local stamps in the begining, then 4(x-250)= x-76, 3x=924, x=308

Edited November 1, 2010 by Tattarrattat
add alternative method: x=local stamps in the beginning

[trisharog]

thx everyone!

[Testimony]

First, he estimated about 300 as the answer.

Next, he figured that 2X+250-76=2x+174

Then, he divided 174 by 3 because of this bar diagram:

[][][][/] He cancelled the last bar here.

[/] He cancelled this bar. That's how he got 3 bars.

 

He got 58 when dividing 174/3. Then he multiplied 58X4=232+76=308. So, it was close to the estimation.

 

Just another way of looking at it based on a 12 year old's thinking.

 

Blessing in your homeschooling journey.

 

Sincerely,

Karen

http://www.homeschoolblogger.com/testimony