Janice has been saving part of her allowance in a bag every month. The bag containing $2 and $10 notes had a total value of $1344. 8 pieces of $10 notes were exchanged for $2 notes of the same value. In the end, the number of $10 notes was the same as the $2 notes. How many $2 notes were there at first?
Let the original number of 2-doallar bills==T
Let the original number of 10-dollar bills==N
2T + 10N ==1344......................(1)
[N + 8] == [T - 40].....................(2), solve for T, N
T ==152 - original number of 2-dollar bills
N ==104 - original number of 10-dollar bills.
