Interesting video

[Graves]

I also had the money for a calculator, however I play tetris on my TI-86

Same here, only mine can view sites like this one

[KevDen2005]

My TI-86 definitely cannot visit sites-even this one...so I am super impressed.

[Irving]

That was the other thing about getting the Casio instead of the Texas Instruments. I never had any games. My calculator had a bunch of cool other programs built in though, that's how I learned about Mandelbrot.

Anyway, since we're talking about math, can someone help me with something?

I've never been able to figure out how to do the other half of percentage problems.

For example I know how to find the percentage of any number. Like 20% of 180 = 180x.20 = 36. So the price of a $180 product after a 20% discount would be $144.

I have a problem figuring out problems like this one:

"Including a 5% tax, you pay $170 for an item. The wholesale cost of the product is 20% less than retail price. How much did the store pay for the item?"

So you can't just subtract 5% from $170, then subtract 20% from that, because that's not the way it works. Can someone help me out with how to solve that kind of problem?

Thanks.

[Holy Diver]

that is completely retarded. How are the Chinese taking our engineering jobs when they're being taught this crap? and Yes.. out of curiosity I tried it for myself.. took 8 times as long as classic multiplication lol.

[Irving]

It's not a current method silly. It is probably ancient Chinese.

Can anyone help me with my question? Do I need to explain it better? I figure one of you programmers is good at math.

[Holy Diver]

"Including a 5% tax, you pay $170 for an item. The wholesale cost of the product is 20% less than retail price. How much did the store pay for the item?"

So you can't just subtract 5% from $170, then subtract 20% from that, because that's not the way it works. Can someone help me out with how to solve that kind of problem?

Thanks.

little soft on the old 7th grade algebra aye? heh

w= wholesale price, r= retail price
170=r*1.05 => r=170/1.05 => r=161.905
r=w*1.2 => w= r/1.2 => w=134.921

Now with that good karma under my belt somebody should be answering my DPMS LR308 problem shortly

[Irving]

Yes, that's what I said. The last "A" I got in math was 6th grade. I don't think your math is correct though, which is the point I was trying to make. 5% of 170 is different than X+5% of X = 170.

100 + 25% of 100 = 125.

But 25% off of 125 is 93.75.

[Holy Diver]

nope. It's correct. you answered your own question. 125% of 100 is different than 75% of 125. you are not looking for 5% off of total cost to find retail, you are looking for the retail cost that when 5% is added you arrive at your total cost.

[Irving]

I must not have looked at your math very well last night, as now I see what you did and it makes perfect sense. I for sure have a problem with algebra. Thanks for working it out.