Joelle made puffs for sale. 60% of the puffs were curry puffs and the rest were sardine and egg puffs in the ratio 3 : 1. If a customer bought 60% of the curry puffs and all of the egg puffs, what percentage of the sardine puffs must Joelle sell for her to maintain the original percentage of curry puffs at first? Leave your answer in decimals and correct to 1 decimal place.

Curry puffs	Sardine puffs	Egg puffs
3 u	2 u
	1.5 u	0.5 u

	Curry puffs	Sardine puffs	Egg puffs	Total puffs
Before	3 u	1.5 u	0.5 u	5 u
Change	- 1.8 u	- 0.7 u	- 0.5 u
After	1.2 u	0.8 u	0	2 u

60% = ⁶⁰₁₀₀ = ³₅
60% = ⁶⁰₁₀₀ = ³₅

Total number of puffs = 5 u

Number of sardine and egg puffs
= 5 u - 3 u
= 2 u

Number of sardine puffs at first
= ³₄ x 2 u
= 1.5 u

Number of egg puffs at first
= 2 u - 1.5 u
= 0.5 u

Number of curry puffs sold
= 60% x 3 u
= ⁶⁰₁₀₀ x 3 u
= ³₅ x 3 u
= 1.8 u

Number of egg puffs sold
= ¹₄ x 2 u
= 0.5 u

Number of curry puffs left 
= 3 u - 1.8 u
= 1.2 u

To maintain the percentage of the curry puffs in the end, 
60% → 1.2 u
100% → ^1.2₆₀ x 100 = 2 u

Total number of puffs in the end to maintain the original percentage of curry puffs = 2 u

Number of sardine puffs left
= 2 u - 1.2 u
= 0.8 u

Number of sardine puffs that Joelle must sell to maintain the original percentage of curry puffs
= 1.5 u - 0.8 u
= 0.7 u

Percentage of the sardine puffs that Joelle must sell
= ^0.7_1.5 x 100%
= 46.7%

Answer(s): 46.7%