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MAS1
05-08-2012, 09:52 AM
Daniel says to Sydney, "If you give me \$2 of your money, we will each have the same amount of money." Sydney responds, "That's true, but on the other hand if you give me \$2 of your money, I will have twice as much money as you."

Question: How much money did Daniel and Sydney each have?

05-11-2012, 07:20 PM
Daniel says to Sydney, "If you give me \$2 of your money, we will each have the same amount of money." Sydney responds, "That's true, but on the other hand if you give me \$2 of your money, I will have twice as much money as you."

Question: How much money did Daniel and Sydney each have?

Let Daniel's money be d, Sydney's money be s.

d + 2 = s - 2
2(d - 2) = s + 2

Simultaneously solve the equations:
d = s - 4
2((s - 4) - 2) = s + 2
2(s - 6) = s + 2
2s - 12 = s + 2
s - 12 = 2
s = 14

Sub it in:
d + 2 = 14 - 2
d + 2 = 12
d = 10.

Sydney has \$14, Daniel has \$10.

MAS1
05-12-2012, 11:05 AM
You are right!