Need some math help

[sailor3X7]

I am helping my daughter with her 8th grade math and I am stuck. We are working on a word problem. We have to give not only the answer but the equation to solve it too.<br />Here's the problem:<br />Karen sells children's hats for $4 and adults' hats for $7. On Saturday, she sold 120 hats, and she collected $720. How many adults' hats did she sell?<br /><br />If you can help us know how to solve this we will be very thankful. I thought of iboats for the solution because my boat is on my mind. Once I solve this, I am taking the boat in to be winterized and a few other maintenance issues.<br />Thanks for your help.

 

[jims plan b]

Re: Need some math help

i know how to do it ..i just cant

 

[sailor3X7]

Re: Need some math help

dang!

 

[one more cast]

Re: Need some math help

I ask my daughter and this is her reply...<br />Shawna says:<br />i'm thinking you set up 2 equations..... 4x + 7y=720 and x+y=120 then you solve for x....x=120-y then you substitute 120-y into the first equation so you have 4(120-y)+7y=720 then solve for y that will telll you how many adult hats were sold.<br />.<br />.<br />. Now the redneck way I would do it is figure out how many 7 you can get out of 720 with a remander that is devisible by 4.<br />.<br />.<br />Shawna says:<br />did my equations make sense...it comes out to be 80

 

[jims plan b]

Re: Need some math help

you need to have <br /><br /> $7.00 X _y_ = _w_<br /> $4.00 X _y_ = _w_<br /><br />W + W needs to add up to $720.00<br /><br />Y + Y needs to add up to 120

 

[jims plan b]

Re: Need some math help

RIGHT!!! I THINK, MAYBE, COULD BE......hummmm

 

[AMD Rules]

Re: Need some math help

OMC (Shauna) gets an A+

 

[grotmeister]

Re: Need some math help

its 80 adults hats and 40 childrens hats but we still workin on a formula here!

 

[CJY]

Re: Need some math help

Shawna is correct. All the math works.

 

[alden135]

Re: Need some math help

What color hats?

 

[KRS]

Re: Need some math help

Originally posted by alden:<br /> What color hats?

There is one in every group isn't there....

 

[one more cast]

Re: Need some math help

Thanks AMD rules and CJY, she is majoring in math/science at Binghamton university. Thats a pretty tough question for 8th grade I would think.

 

[sailor3X7]

Re: Need some math help

Thanks to all (especially Shawna)<br />We appreciate the help.<br />Alden... I can relate to your answer.<br />When everyone is discussing something deep I usually have response like, "you know, this reminds me of something that happened on Gilligan's Island once."

 

[lakelivin]

Re: Need some math help

correct, another way to visualize it:<br /><br />c = the number of childrens hats sold<br />a = the number of adults hats sold<br /><br />we have two equations:<br /> c + a = 120<br />4c + 7a = 720 (4 & 7 being their respective prices, 720 being the total amount collected)<br /><br />since c + a = 120, multiply both sides of the equation by 4 to get 4c + 4a =480<br /><br />still have two equations with two unknowns, so subtract the bottom from the top:<br /> (4c + 7a = 720)<br /> - (4c + 4a = 480)<br /> ______________<br />leaving 0 + 3a = 240<br /><br />or a = 240/3 = 80<br /><br />we know c + a = 120, so c + 80 = 120 and therefore c = 120 - 80 = 40

 

[one more cast]

Re: Need some math help

Wouldn't it be easier just to check your inventory?

 

[stan_deezy]

Re: Need some math help

Originally posted by One More Cast:<br /> Wouldn't it be easier just to check your inventory?

Yeah and did the seller declare the sales taxes

 

[Kenneth Brown]

Re: Need some math help

Originally posted by One More Cast:<br /> Wouldn't it be easier just to check your inventory?

They would have but the light bulb was out.

 

[dogsdad]

Re: Need some math help

Great. So new we gotta figure out how to change a light bulb? This is getting out of hand!!

 

[Realgun]

Re: Need some math help

I am so glad I did not have to sell any hats this weekend.