Jade bought some necklaces and rings for her friends. The price of each necklace was $4.70 while the price of each ring was $12.60. 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 Jade paid a total of $1133.60, 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	$12.60	0	$4.70
Total value	264.6 u	0	18.8 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 12.60
= 264.6 u

Cost of the bought necklaces
= 4 u x 4.70  
= 18.8 u

Total cost of the bought items
= 264.6 u + 18.8 u
= 283.4 u

283.4 u = 1133.60

1 u = 1133.60 ÷ 283.40 = 4

Amount that she paid more for the rings than the necklaces
= 264.6 u - 18.8 u 
= 245.8 u
= 245.8 x 4
= $983.20

Answer(s): $983.20