Answer:
70 cards
Explanation:
Let A = the number of Andys cards
J = the number of Jons cards
Jon and Andy had a total of 560 trading cards
A+J = 560
After Jon gave 1/9 of his trading cards to Andy, they has an equal number of trading cards
J - 1/9 J = 1/9 J +A
Combine like terms
8/9 J = 1/9 J +A
Subtract 1/9J from each side
7/9J = A
Substitute this into A +J = 560
7/9J +J = 560
Combine like terms
7/9J +9/9J = 560
16/9 J = 560
Multiply each side by 9/16
9/16 *16/9 J = 560 *9/16
J =315
Jon originally had 315 cards
Now we need to find Andys cards
7/9J = A
7/9 (315) =A
245=A
How many more trading cards did Jon have that Andy in the beginning?
We need to take Jons cards and subtract Andys cards
J-A
315-245
70