Natalie made puffs for sale. 45% of the puffs were kaya puffs and the rest were egg and chocolate puffs in the ratio 3 : 1. If a customer bought 60% of the kaya puffs and all of the chocolate puffs, what percentage of the egg puffs must Natalie sell for her to maintain the original percentage of kaya puffs at first? Leave your answer in decimals and correct to 1 decimal place.

Kaya puffs	Egg puffs	Chocolate puffs
9 u	11 u
	8.25 u	2.75 u

	Kaya puffs	Egg puffs	Chocolate puffs	Total puffs
Before	9 u	8.25 u	2.75 u	20 u
Change	- 5.4 u	- 3.85 u	- 2.75 u
After	3.6 u	4.4 u	0	8 u

45% = ⁴⁵₁₀₀ = ⁹₂₀
60% = ⁶⁰₁₀₀ = ³₅

Total number of puffs = 20 u

Number of egg and chocolate puffs
= 20 u - 9 u
= 11 u

Number of egg puffs at first
= ³₄ x 11 u
= 8.25 u

Number of chocolate puffs at first
= 11 u - 8.25 u
= 2.75 u

Number of kaya puffs sold
= 60% x 9 u
= ⁶⁰₁₀₀ x 9 u
= ³₅ x 9 u
= 5.4 u

Number of chocolate puffs sold
= ¹₄ x 11 u
= 2.75 u

Number of kaya puffs left 
= 9 u - 5.4 u
= 3.6 u

To maintain the percentage of the kaya puffs in the end, 
45% → 3.6 u
100% → ^3.6₄₅ x 100 = 8 u

Total number of puffs in the end to maintain the original percentage of kaya puffs = 8 u

Number of egg puffs left
= 8 u - 3.6 u
= 4.4 u

Number of egg puffs that Natalie must sell to maintain the original percentage of kaya puffs
= 8.25 u - 4.4 u
= 3.85 u

Percentage of the egg puffs that Natalie must sell
= ^3.85_8.25 x 100%
= 46.7%

Answer(s): 46.7%