A simple problem.,

if

abc = 10
acd = 5
abd = 45
bcd = 12

what is a + c?

Question

A simple problem.,

if

abc  = 10
acd  = 5
abd  = 45
bcd  = 12

what is a + c?

anonymous · Answer

i'm useless here .. brb

anonymous · Answer

No offense but: don't be expecting an answer on OS if you have no dedication of trying in the first place.

callisto · Answer

@Noliec I think shai is not that kind of person

anonymous · Answer

If that is the case then I apoligize.

apoorvk · Answer

@Noliec  you are probably mistaken. She posts some really good problems, and is way more genius than a lot of us (atleast me) :)

anonymous · Answer

This could be relatively easy solved with matrices.

anonymous · Answer

multiply them all together to get (abcd)^3.  from there you can figure out what a, b, c, and d are individually.

anonymous · Answer

@joemath314159 that can help a lot .. thanks

anonymous · Answer

then abcd = 30 .. ?

callisto · Answer

I think so

anonymous · Answer

Yep, 30

anonymous · Answer

abc = 10, abcd/d = 30/d = 10 --> 30 = 10 d --> d = 3

anonymous · Answer

@Noliec i want to learn, that's why i'm here in OS

anonymous · Answer

I am sorry, I misinterpreted your first reply to this question. :)

anonymous · Answer

in this case, there's no need to solve for the values of b and d right?

anonymous · Answer

i think i figure it out now,.. hmmm

callisto · Answer

You can do so, but not necessary, I think...

anonymous · Answer

So a = 5/2, b = 6, c = 2/3, d = 6.
a+c=19/6

anonymous · Answer

@Recursing you're smart! Next problem .. lol