Peter had 65% fewer chocolate bars than Riordan. After Riordan gave 380 chocolate bars to Peter, Peter had ²₃ as many chocolate bars as Riordan. How many chocolate bars did each of them have in the end?

1. Riordan
2. Peter

	Peter	Riordan	Total
Before	7x5 = 35 u	20x5 = 100 u	27x5 = 135 u
Change	+ 380	- 380
After	2x27 = 54 u	3x27 =  81 u	5x27 = 135 u

Number of chocolate bars that Peter had at first in percentage
= 100% - 65%
= 35%

35% = ³⁵₁₀₀ = ⁷₂₀

The total number of chocolate bars at first and in the end remains unchanged. Make the total number of chocolate bars the same. LCM of 5 and 27 is 135.

Number of chocolate bars that Riordan gave to Peter
= 100 u - 81 u
= 19 u

19 u = 380

1 u = 380 ÷ 19 = 20

Number of chocolate bars that Peter had in the end
= 54 u
= 54 x 20
= 1080

Number of chocolate bars that Riordan had in the end
= 81 u
= 81 x 20
= 1620

Answer(s): (a) 1080; (b) 1620