What is the meaning of the \sum signal in this direct current circuit problem?

[zvee_y]

I've attached the problem in this post, so that's way yall can see the problem and picture easily.

The Attempt at a Solution

what is this signal $$\sum$$ means in the problem?
THe problem said they find the ammeter in the cirucuit read 2A, I just wonder is it the total current?
If i set up I = I1 + I2, then in loop 1 (top loop) I can use I and I1 to; and in loop 2(bottom loop) I can use I and I2 in order to find the currents. Is it correct? Please give me a hint. Thank you!

 

[mgb_phys]

The symbol is a capital Sigma, it generally means sum of ( ie add them all up )
ps - You don't seem to have attached the picture properly

 

[zvee_y]

Thanks. I did fixed the picture. Can anyone please help me out?

 

[kamerling]

define the potential to the point to the right of the ammeter to be 0.
call the potential to the left of th 5 ohm resistance U.
What must U be to make the current through the ammeter equal to 2A?
Once you have U you can calculate I_1 and the use kirchhof's current law to get I_2

 

[Snazzy]

Go around the bottom loop and go around the top loop using Kirchoff's loop law, then find I3 through the ammeter in terms of I1 and I2. 3 equations and 3 unknowns.

 

[kinnee2000]

I want answer for questions, wuold you help mme?

 

[Defennder]

Unfortunately no one can give you the answer, per PF rules. Show your work and we'll help you if you have problems.