Maths question for you all...!
 

The avg. (arithmetic - mean) of a and b is ninety; the avg. (arithmetic mean) of a and c is 150; what is the total value of (b-c)/2?

Three fiddy.

quick bitches!

-60





...........

You can't solve something like this you have one equation with two unknowns. Because arithmetic average of a and b is ((a+b)/2) and you said it's 90, but you don't know from this, what is a or b
And the same is is valid for c and d, of course.

there is no D.... unless he is seeking the sum of D as to which I thought would be X

Macs suck!

Math makes my brain hurt

you just subtract 2nd equation from the first... :2 cents:

(a+b)/2=90
(a+c)/2=150
-------------------
((a+b)-(a+c))/2=90-150
(a+b-a-c))/2=-60
(b-c)/2=-60

You may be dead on, or dead wrong. I am too old to remember these equations. If I had to guess though, I would say you were RIGHT!

this is correct, and I said it already a few posts up :thumbsup

Fuck, I didn't read it properly, in this case I agree with " d-null " it's -60

Gets my vote...

solution without proof is useless... :2 cents::winkwink:

it's whatever the rothchilds and rockefellars say it is!

you are right, I thought it too simple to bother :winkwink:

a+b=180
a+c=300

a=180-b
a=300-c

180-b=300-c

-b=120-c

b=c-120

(b-c)/2


(c-120-c) /2

-60

(a+b)/2=90
(a+c)/2=150

a+b=180
a+c=300

a=180-b
c+180-b=300

c-b=120
-120=b-c
-60=(b-c)/2

My math teachers would give us an F if we didn't "write it out".

And.... wait for it.... wait for it... most of us ARE simple. lmao

Reading this thread I see why so many people ask to explain what is the ratio column in our affiliate report and how it is calculated.

(a+b)/2=90; (a+c)/2=150
(a+b)/2=((a+c)/2)-60
a/2 + b/2=a/2 + c/2 -60
b/2=c/2 -60
b/2-c/2=c/2-c/2-60
(b-c)/2=-60

tube sites

at least 5 different methods

22.5

Fucked if I remember how I came to it...

where are the bones ?

That's how I want to die.

Or in my case arithmetically challenged. :Oh crap

.

Years and years ago there was a software you could feed the two starting equations to and it would do all the steps and writing it out for you. I think it ran on my Apple ][ (yes, showing my age) - anybody remember what it was called?