Question 586293
Bill, Joe & Cindy each have money. 
Together Bill and Joe have $18. 
b + j = 18
:
Together Joe and Cindy have $21.
j + c = 21
j = (21-c)
:
together Bill and Cindy have a total of $23.
b + c = 23
b = (23-c)
;
How much money does each individual have?
Replace b and j in the 1st equation
(23-c) + (21-c) = 18
-2c + 44 = 18
44 - 18 = 2c
26 = 3c
c = 26/2
c = 13
then
j = 21 - 13
j = 8
and
b = 23 - 13
b = 10