Pizza math

[eveled]

I teach at a trade school at night. First year plumbing. Believe it or not plumbing is very math heavy.

These aren’t really kids, ages range from 25 to 50. They all struggle with fractions. I relate it all to pizza. 2 guys buy a pizza and share it. You ate 1/2 and he ate 1/2. See you use fractions every day.

The pizza is cut up into 8 slices. I have 3 you have 5. I had 3/8 of the pie, you had 5/8. The bottom number is how many slices it is cut into, the top number is how many slices you got. Easy peasy.

Now 5 divided by 8 = .625 move the decimal place over 2 you ate 62.5% of the pizza.

I think they get it! I’m making progress! I’m making a difference in the world! Yay! (I’m actually really excited at this point.)

Now we have a gross of ball valves. We used 70 of them. What percentage is left over. All I get is blank stares. My heart sinks, they don’t get it I’m a failure. Then I realize, none of them even know what a gross is. Lol.

It’s fun to teach, but frustrating too. When you see the light come on and the blank stare becomes an excited look of enlightenment. It’s pretty cool.

 

[Mobuck]

Now days, most people think that's what a phone's for.
When I conduct a "new hire" interview and competency test, phones/calculators are not allowed. I watch the candidate to see how he'/she handles the math questions and it's a fairly good indicator of how successful or effective the candidate will be. I have an employee with an 8th grade education, one with a Masters degree, and one PhD. The one with a grade school education quit school because he simply couldn't learn(and he still can't). He functioned by rote through out his entire life and any attempt to teach him something new requires continual coaching.
If you tried to use "pizza math" on him, he'd tell you he doesn't like pizza and return to his own version of reality. I'll be glad to see him retire.

 

[contender]

Schools no longer fail students,, or make them EARN a grade.

I saw a news program the other night,, about the remote learning currently going on. It was about how students were "falling behind" and "not learning the material." The answer to the issuer was to "re-evaluate the grading standards into a curve." Basically, reduce the requirement to learn.

Dumbing down America.

 

[blume357]

Long time ago I was a member of the U.S. Power Squadron... and took almost all their courses... Celestial Navigation was interesting... spherical trigonometry and having to interpolate.

 

[GunnyGene]

I teach at a trade school at night. First year plumbing. Believe it or not plumbing is very math heavy.

These aren’t really kids, ages range from 25 to 50. They all struggle with fractions. I relate it all to pizza. 2 guys buy a pizza and share it. You ate 1/2 and he ate 1/2. See you use fractions every day.

The pizza is cut up into 8 slices. I have 3 you have 5. I had 3/8 of the pie, you had 5/8. The bottom number is how many slices it is cut into, the top number is how many slices you got. Easy peasy.

Now 5 divided by 8 = .625 move the decimal place over 2 you ate 62.5% of the pizza.

I think they get it! I’m making progress! I’m making a difference in the world! Yay! (I’m actually really excited at this point.)

Now we have a gross of ball valves. We used 70 of them. What percentage is left over. All I get is blank stares. My heart sinks, they don’t get it I’m a failure. Then I realize, none of them even know what a gross is. Lol.

It’s fun to teach, but frustrating too. When you see the light come on and the blank stare becomes an excited look of enlightenment. It’s pretty cool.

Show them this, see if they can figure it out: :wink:

 

[314Chevy]

To be fair had to google how many a gross was (144).

 

[Cholo]

↑ If you bought Cherry Bombs in bulk as a kid like we did, you would have learned what a gross was at a young innocent age It's not a word used much anymore.

 

[JFB]

given they didn't know the term "gross" need to tell them that number of items
comes from a dozen, dozens and see if the calculators, oops, I should say PHONES,
come out to punch in those for the answer

 

[Snake45]

Dumbing down America.

Been happening for decades. And it looks like Stupid America has just elected a leader. :lol:

 

[GunnyGene]

Dumbing down America.

Been happening for decades. And it looks like Stupid America has just elected a sock puppet :lol:

FIFY. :wink: :lol:

 

[Dave P.]

Dumbing down America.

Been happening for decades. And it looks like Stupid America has just elected a leader. :lol:

Collectively America has decided out of ALL the people in this country ( well at least those dumb enough to
want the job ) that he was the very best we have, to lead one of earth's most powerful countries.....
"Stupid America", what an understatement!
I'll apologize in advance for continuing the thread drift off the OP's post.
Seems unavoidable lately.
Dave

 

[Bull Barrel]

Heck, people today think a half gallon is 48 oz.

 

[NikA]

My personal take on the math literacy problem in America: it's not a learning problem, it's a problem with the ability of young individuals being able to identify skills that might be useful to them in the future.

Almost everyone has the ability to learn basic math. But phones and calculators have made learning basic math less and less necessary, and since most school-aged people haven't identified a career, their first reaction is "I ain't gonna need this" and they promptly ignore/forget it.

Sadly, I saw this attitude every when teaching intro engineering courses to future engineers during my graduate education. If it wasn't their "flavor" of engineering, many regarded learning it as a burden not worth their time.

I also think the anti-education attitude in the United States is partially to blame. Look at how average folks tend to disparage university education as a leftist ploy/indoctrination. That attitude is likely to permeate to young impressionable students who think "people will not respect the work I put in to getting a professional education".

 

[Kevin]

Eveled: Good for you for using real world examples to make your students learn!

↑ If you bought Cherry Bombs in bulk as a kid like we did, you would have learned what a gross was at a young innocent age It's not a word used much anymore.

Oh yes, every time I see the word gross, relating to quantity, the first thing I think of is a big package of fire crackers.

 

[dad45]

Just pick up a grade school math book from the forties, fifties or there about and see what was being taught then vs. now and the problem will be evident, as someone noted above trying to get many of the current youth to understand the need for these skills or care can be monumental, which makes an instructors job difficult to say the least

 

[eveled]

That level is pretty cool! Invent one that sticks to copper pipes and I’ll take 1!

Yes I realize now not everyone knows what a gross is, but the look on their faces scared me when I looked up. Once I told them it was a dozen dozen or 144 pieces the little lights came back on in their eyes, and I felt better. I’m going to use the cherry bomb case for an example. Usually it’s 12 in a box, 12 boxes in a case.

I have the advantage that they want to learn, and want to be plumbers someday, their final exam is in 5 years when they take their license test.

A gross is not used often, almost like score, or fortnight.

 

[coach]

Time to whip out the old Texas Instruments calculator. Or maybe my phone.

 

[eveled]

They can use calculators but not their phones.

You still need to know what to put into it.

 

[GunnyGene]

That level is pretty cool! Invent one that sticks to copper pipes and I’ll take 1!

A couple small bungees works pretty well. Picked this up at a yard sale several years ago just because old tools interest me.

As an aside, most construction fields going back to ancient times (10,000 years or more) require a good understanding of math - including fractions and angles. If you didn't have it you hauled the rocks and dug the ditches. Same as today. :wink:

 

[Colonialgirl]

Had a gross of valves = 144
Used 70 ,,,,,,,,,,,,,,,,,,, - 70
Leaves ========== 74
what percentage of valves are left?

74/144 = 0.51388889 or 51.38889 % but to get to the percentage required LONG division and my calculator was much quicker and handy for that

 

[Ale-8(1)]

Yep, "scientific" calculators revolutionized the engineering world. But just like the slide rules they replaced ya gotta know how to use them. :wink:

 

[arfmel]

Young people may not have the math skills they need, but at least they’ve been taught how to put a condom on a banana.

 

[redhawker]

Now days, most people think that's what a phone's for.

Well, I do remember when I was in high school calculators were a new thing and we were forbidden to use them in class. If I remember right a good calculator was around $150 - $200 back then too. It was actually a good thing we couldn't use them in class, but the stated reason, "you're not going to have a calculator with you all the time" doesn't ring true anymore. I dare say most of us have a phone, calculator, camera, computer, etc. on us almost 24/7 anymore.

 

[GunnyGene]

Now days, most people think that's what a phone's for.

Well, I do remember when I was in high school calculators were a new thing and we were forbidden to use them in class. If I remember right a good calculator was around $150 - $200 back then too. It was actually a good thing we couldn't use them in class, but the stated reason, "you're not going to have a calculator with you all the time" doesn't ring true anymore. I dare say most of us have a phone, calculator, camera, computer, etc. on us almost 24/7 anymore.

I reckon I'm not most. Don't have any of that I carry around. I do have a computer (obviously). And I have a couple of calculators I use occasionally. But I can do without any of that quite well.

But what I like the most is this. Fits in a pocket and doesn't require batteries.

I also have an M2 compass from WWII for navigation. And a shop full of unpowered tools. So what does all that mean? It means I'm not dependent on some fancy electronics for my survival and day to day life.

 

[Rick Courtright]

To be fair had to google how many a gross was (144).

Hi,

No, it's not, it's 12 dozen! [sarc] An example of today's thinking among a lot of young people which doesn't even allow for a couple of names to represent the same thing.

I wonder: how many of the OP's students are gonna be pushing 300 lbs before they get thru the class?

Rick C

 

[sceva]

I went back to school for a Quality Engineering degree in my 40's, lots of Trig etc. They asked for volunteers to tutor and I was shocked to get people just out of high school taking remedial math and not being able to multiply unless the used their " Multiplication Sheet" where they looked at where the two numbers crossed to find the answer.
Don't even get me started on "Common Core" math other than to say I sure won't be able to help my Grandsons when they start taking it.

 

[exavid]

I'm convinced it's the variety of crap teachers throw at kids these days. getting an answer to a simple problem using 'Common core'. What a load of crap.

I left high school in my senior year so didn't have a full course of mathematics. I learned a goodly lot of it working as an electronic technician after two years of electronics training at a tech school . Most of my working career required a good ability to use a slide rule to figure out antenna lengths, values for the components to make an oscillator that would generate a given frequency, or calculate the lentgh of an antenna for a given the length of an antenna for a transmitter. Lots of different calculations for different types of antenna types to match the type and frequency and many other things to make sure a glide slope and localizer were working and providing accurate angle and compass bearing to aircraft operating in Instrument conditions.

I don't believe I could have mastered the trade if I'd had the type of math that is being taught to kids like my grandson. Ever look at any "Common Core" crap they use teaching math in schools now? Our kids are going to have a heck of a time learning math for any engineering or laboratory work.

 

[Rick Courtright]

Hi,

For a combination of reasons, my geometry background is horrid, and it affected the rest of my HS math (Algebra II, Trig and Calculus.) In cleaning out my father's stuff when he passed, we found his HS geometry book. I asked Mom if anyone had laid claim to it, and they hadn't, so she gave it to me. I looked thru it, then the next time I got together with a buddy whose math background is as good as mine is bad, I had him look at it.

He hired dozens of people during his working years, all of whom had good math skills. I asked where he'd put the mid-1940s geometry book in the grand scheme of things. He suggested a college geometry class today would probably fall short by about a quarter of that book. Later, my brother gave me our Mom's calculus book when she passed. I took what they called calculus in HS--in retrospect probably just an introductory class--and actually soaked up enough to be able to help a couple of college roommates the first couple of weeks when they took their first college calculus class. I wonder how many college classes it would take to cover that "also 1940s" HS book?

Rick C

 

[eveled]

I wonder: how many of the OP's students are gonna be pushing 300 lbs before they get thru the class?

Rick C

I don’t know what prompted that remark? Because they know a pizza gets cut into slices?

These are young tradesmen, working hard to better themselves and doing the heavy work the apprentices get stuck with. Not one of them is out of shape. Their instructor is another story.

 

[caryc]

I wonder: how many of the OP's students are gonna be pushing 300 lbs before they get thru the class?

Rick C

I don’t know what prompted that remark? Because they know a pizza gets cut into slices?

These are young tradesmen, working hard to better themselves and doing the heavy work the apprentices get stuck with. Not one of them is out of shape. Their instructor is another story.

Speaking of Pizza math...A guy goes into a shop to get a pizza. The man asks him if he wants it cut into 6 pieces or 8 pieces. He replies, "Better make it 6, I don't think I can eat 8.