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martin
01-04-2011, 11:40 AM
Hi,

I'm mathematically illiterate so I'd appreciate any help with the following query, laughably simple though it may be.

I have a ratio of 60:40.

The value for 40 is, let's say, 12.

How do I calculate the value for 60?

Sincerest thanks, Martin

droid
01-04-2011, 11:45 AM
You nearly had me there.

martin
01-04-2011, 11:45 AM
It's not an April Fool! I knew I should have posted this yesterday...

droid
01-04-2011, 11:48 AM
lol

40 and 60 are both divisible by 20.

If 40=12 then half of 40 is 20 which =6

If 20=6 then 3x20=60 and 3x6=18

So the solution is 60:40 = 18:12

Im sure theres a much cleverer way, but thats how Id do it..

john eden
01-04-2011, 11:49 AM
I'm a bit rusty but here goes...

60:40 = 6:4 basically?

So the question is what do you have to do to 4 to turn it into 6.

I.e 4 X 1.5 = 6

john eden
01-04-2011, 11:50 AM
So...

12 x 1.5 = 18.

40 x 1.5 = 60

a x 1.5 = b

etc.

droid
01-04-2011, 11:51 AM
So...

12 x 1.5 = 18.

40 x 1.5 = 60

a x 1.5 = b

etc.

Yeah, thats the clever way. Swot.

john eden
01-04-2011, 11:53 AM
Yeah, thats the clever way. Swot.

I've still got it.

Where "it" = a tenuous grasp of 'A' level maths.

Chicks go crazy for this shit.

martin
01-04-2011, 11:55 AM
Ah OK, I actually get it! I think.

So if the 40 was 23.5, the 60 would be 35.25...right?

droid
01-04-2011, 11:57 AM
Ah OK, I actually get it! I think.

So if the 40 was 23.5, the 60 would be 35.25...right?

Yep.

john eden
01-04-2011, 12:00 PM
That's it.

Actually, in my defence I have been helping Eden Jnr with her maths homework on and off so I guess my nerdery is useful at that level!

martin
01-04-2011, 12:01 PM
Cool, many thanks to both of you. So we can conclude that the Woofah editors are the best mathematicians on Dissensus - knew it all along...

I'm just doing ratios like crazy now, with a smug grin on my face. Nobody at work seems remotely impressed.

john eden
01-04-2011, 12:05 PM
Cool, many thanks to both of you. So we can conclude that the Woofah editors are the best mathematicians on Dissensus - knew it all along...

I'm just doing ratios like crazy now, with a smug grin on my face. Nobody at work seems remotely impressed.

They FEAR the ratio and your CONQUEST of it, Martin.

They will speak of you in awed hushed tones when you leave the room.

:cool:

Mr. Tea
01-04-2011, 12:06 PM
Ah OK, I actually get it! I think.

So if the 40 was 23.5, the 60 would be 35.25...right?

Yeah, sounds right. It's 23.5 * 1.5.

It's funny, I am an official unemployed now so I'll probably go back to tutoring until I find something proper...*self-pimps*

droid
01-04-2011, 12:18 PM
Yeah, sounds right. It's 23.5 * 1.5.

It's funny, I am an official unemployed now so I'll probably go back to tutoring until I find something proper...*self-pimps*


You could become Martin's personal maths tutor, it'll be like Pygmalion except with Maths.

Mr. Tea
01-04-2011, 12:21 PM
You could become Martin's personal maths tutor, it'll be like Pygmalion except with Maths.

I was kind of thinking that...just sounds too much the premise for a really contrived sitcom.

martin
01-04-2011, 12:31 PM
Yeah, the scene where Ted and Dougal are trying to write the Eurovision song did just spring to mind...

"No, it's a fraction! A fecking fraction! Just times it by the fecking number! A quarter! A fecking quarter!"

"Uhhh...times by 1.5?"

Slothrop
01-04-2011, 01:00 PM
I'm a bit rusty but here goes...

60:40 = 6:4 basically?

So the question is what do you have to do to 4 to turn it into 6.

I.e 4 X 1.5 = 6

The really mathsy way of putting it is that if things are in a ratio of 60 : 40 and you want "40=12"
you're saying "for what x is 60:40 the same as x:12?"
You can read a:b as a/b, so this means
For what x does
60/40 = x/12
or
3/2 = x/12
Rearrange:
12*3/2 = x
Simplify:
18 = x

But John's approach is probably easier to remember and works.

Anyway, I'm sure someone will be along soon to berate us for our slavish devotion to blind enlightenment rationalism...

alex
04-04-2011, 09:21 AM
this has nothing to do with ratios but

In school I was always told the importance of putting decimal points in the right places when calculating numbers or stating a total figure or whatever, however when I receive some quotations in my job, they read:

10.000,00 (to read £10,000.00)

By the school’s logic, that to me, read’s £10.00

so basically, that’s bullshit.

edit* although looking at similar quotes I'm recieving, I think it's a continental thing, and we, the british have it arse about face?

baboon2004
04-04-2011, 12:36 PM
france and iceland use dots rather than commas, probably elsewhere too....almost made a massive fuck-up on a cash machine because of this....


this has nothing to do with ratios but

In school I was always told the importance of putting decimal points in the right places when calculating numbers or stating a total figure or whatever, however when I receive some quotations in my job, they read:

10.000,00 (to read £10,000.00)

By the schoolís logic, that to me, readís £10.00

so basically, thatís bullshit.

edit* although looking at similar quotes I'm recieving, I think it's a continental thing, and we, the british have it arse about face?

Mr. Tea
04-04-2011, 01:03 PM
I think "10.000,00" for "10,000.00" is standard in most of Europe. What's also odd is seeing something priced (say) 2 euro 50 labelled "2.5-" instead of "2.50".

baboon2004
04-04-2011, 02:07 PM
Hi,

I'm mathematically illiterate so I'd appreciate any help with the following query, laughably simple though it may be.

I have a ratio of 60:40.

The value for 40 is, let's say, 12.

How do I calculate the value for 60?

Sincerest thanks, Martin

Sorry if someone already said this, but just 60/40 x 12 (= 3/2 x 12 int his case), so a/b x c as a generalised form.