Wendy bought some rings and necklaces for her friends. The price of each ring was $4.20 while the price of each necklace was $14.30. For every 7 necklaces bought, she was given one such ring for free. After receiving the free rings, the number of rings was ¹₅ of the number of necklaces bought. If Wendy paid a total of $4071.20, how much more did she pay for the necklaces than the rings?

Necklaces	Rings
5x7	1x7
Bought	Free	Bought
7x5	1x5
35 u	5 u	2 u

	Necklaces	Rings
	Bought	Free	Bought
Number	35 u	5 u	2 u
Value	$14.30	0	$4.20
Total value	500.5 u	0	8.4 u

The number of necklaces bought is the repeated identity. Make the number of necklaces bought the same.  LCM of 5 and 7 is 35.

Cost of the bought necklaces
= 35 u x 14.30
= 500.5 u

Cost of the bought rings
= 2 u x 4.20  
= 8.4 u

Total cost of the bought items
= 500.5 u + 8.4 u
= 508.9 u

508.9 u = 4071.20

1 u = 4071.20 ÷ 508.90 = 8

Amount that she paid more for the necklaces than the rings
= 500.5 u - 8.4 u 
= 492.1 u
= 492.1 x 8
= $3936.80

Answer(s): $3936.80