Nicole bought some necklaces and rings for her friends. The price of each necklace was $3.10 while the price of each ring was $14.20. For every 7 rings bought, she was given one such necklace for free. After receiving the free necklaces, the number of necklaces was ¹₃ of the number of rings bought. If Nicole paid a total of $2484.80, how much more did she pay for the rings than the necklaces?

Rings	Necklaces
3x7	1x7
Bought	Free	Bought
7x3	1x3
21 u	3 u	4 u

	Rings	Necklaces
	Bought	Free	Bought
Number	21 u	3 u	4 u
Value	$14.20	0	$3.10
Total value	298.2 u	0	12.4 u

The number of rings bought is the repeated identity. Make the number of rings bought the same.  LCM of 3 and 7 is 21.

Cost of the bought rings
= 21 u x 14.20
= 298.2 u

Cost of the bought necklaces
= 4 u x 3.10  
= 12.4 u

Total cost of the bought items
= 298.2 u + 12.4 u
= 310.6 u

310.6 u = 2484.80

1 u = 2484.80 ÷ 310.60 = 8

Amount that she paid more for the rings than the necklaces
= 298.2 u - 12.4 u 
= 285.8 u
= 285.8 x 8
= $2286.40

Answer(s): $2286.40