Jade made muffins for sale. 40% of the muffins were curry muffins and the rest were chicken and beef muffins in the ratio 3 : 1. If a customer bought 75% of the curry muffins and all of the beef muffins, what percentage of the chicken muffins must Jade sell for her to maintain the original percentage of curry muffins at first? Leave your answer in decimals and correct to 1 decimal place.

Curry muffins	Chicken muffins	Beef muffins
2 u	3 u
	2.25 u	0.75 u

	Curry muffins	Chicken muffins	Beef muffins	Total muffins
Before	2 u	2.25 u	0.75 u	5 u
Change	- 1.5 u	- 1.5 u	- 0.75 u
After	0.5 u	0.75 u	0	1.25 u

40% = ⁴⁰₁₀₀ = ²₅
75% = ⁷⁵₁₀₀ = ³₄

Total number of muffins = 5 u

Number of chicken and beef muffins
= 5 u - 2 u
= 3 u

Number of chicken muffins at first
= ³₄ x 3 u
= 2.25 u

Number of beef muffins at first
= 3 u - 2.25 u
= 0.75 u

Number of curry muffins sold
= 75% x 2 u
= ⁷⁵₁₀₀ x 2 u
= ³₄ x 2 u
= 1.5 u

Number of beef muffins sold
= ¹₄ x 3 u
= 0.75 u

Number of curry muffins left 
= 2 u - 1.5 u
= 0.5 u

To maintain the percentage of the curry muffins in the end, 
40% → 0.5 u
100% → ^0.5₄₀ x 100 = 1.25 u

Total number of muffins in the end to maintain the original percentage of curry muffins = 1.25 u

Number of chicken muffins left
= 1.25 u - 0.5 u
= 0.75 u

Number of chicken muffins that Jade must sell to maintain the original percentage of curry muffins
= 2.25 u - 0.75 u
= 1.5 u

Percentage of the chicken muffins that Jade must sell
= ^1.5_2.25 x 100%
= 66.7%

Answer(s): 66.7%