Hazel made muffins for sale. 60% of the muffins were egg muffins and the rest were mushroom and chicken muffins in the ratio 4 : 1. If a customer bought 75% of the egg muffins and all of the chicken muffins, what percentage of the mushroom muffins must Hazel sell for her to maintain the original percentage of egg muffins at first? Leave your answer in decimals and correct to 1 decimal place.

Egg muffins	Mushroom muffins	Chicken muffins
3 u	2 u
	1.6 u	0.4 u

	Egg muffins	Mushroom muffins	Chicken muffins	Total muffins
Before	3 u	1.6 u	0.4 u	5 u
Change	- 2.25 u	- 1.1 u	- 0.4 u
After	0.75 u	0.5 u	0	1.25 u

60% = ⁶⁰₁₀₀ = ³₅
75% = ⁷⁵₁₀₀ = ³₄

Total number of muffins = 5 u

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

Number of mushroom muffins at first
= ⁴₅ x 2 u
= 1.6 u

Number of chicken muffins at first
= 2 u - 1.6 u
= 0.4 u

Number of egg muffins sold
= 75% x 3 u
= ⁷⁵₁₀₀ x 3 u
= ³₄ x 3 u
= 2.25 u

Number of chicken muffins sold
= ¹₅ x 2 u
= 0.4 u

Number of egg muffins left 
= 3 u - 2.25 u
= 0.75 u

To maintain the percentage of the egg muffins in the end, 
60% → 0.75 u
100% → ^0.75₆₀ x 100 = 1.25 u

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

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

Number of mushroom muffins that Hazel must sell to maintain the original percentage of egg muffins
= 1.6 u - 0.5 u
= 1.1 u

Percentage of the mushroom muffins that Hazel must sell
= ^1.1_1.6 x 100%
= 68.8%

Answer(s): 68.8%