Kathy had a total of 123 pieces of $2 and $50 notes at first. She spent ³₇ of the number of $2 notes and received another 9 pieces of $50 notes from her mother. After that, the number of $50 notes she had was ¹₂ of the remaining notes. How much money did Kathy have at first?

	$2	$50	Total
Before	7 u	4 u - 9	123
Change	- 3 u	+ 9
After	4 u
Comparing $2-notes and $50-notes	1x4 = 4 u	1x4 = 4 u

The number of $2-notes and $50-notes in the end is the same.

The number of $2-notes in the end is repeated.  Make the number of $2-notes in the end the same. LCM of 1 and 4 is 4.

Number of notes at first
= 7 u + 4 u - 9
= 11 u - 9

11 u - 9 = 123
11 u = 123 + 9
11 u = 132

1 u = 132 ÷  11 = 12

Number of $2-notes at first
= 7 u
= 7 x 12
= 84

Total value of $2-notes at first
= 84 x 2
= $168

Number of $50-notes at first
= 4 u - 9
= 4 x 12 - 9
= 48 - 9
= 39

Total value of $50-notes at first
= 39 x 50
= $1950

Amount that Kathy had at first
= 168 + 1950 
= $2118

Answer(s): $2118