Esther had a total of 35 pieces of $20 and $10 notes at first. She spent ³₇ of the number of $20 notes and received another 9 pieces of $10 notes from her mother. After that, the number of $10 notes she had was ¹₂ of the remaining notes. How much money did Esther have at first?

	$20	$10	Total
Before	7 u	4 u - 9	35
Change	- 3 u	+ 9
After	4 u
Comparing $20-notes and $10-notes	1x4 = 4 u	1x4 = 4 u

The number of $20-notes and $10-notes in the end is the same.

The number of $20-notes in the end is repeated.  Make the number of $20-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 = 35
11 u = 35 + 9
11 u = 44

1 u = 44 ÷  11 = 4

Number of $20-notes at first
= 7 u
= 7 x 4
= 28

Total value of $20-notes at first
= 28 x 20
= $560

Number of $10-notes at first
= 4 u - 9
= 4 x 4 - 9
= 16 - 9
= 7

Total value of $10-notes at first
= 7 x 10
= $70

Amount that Esther had at first
= 560 + 70 
= $630

Answer(s): $630