Shiyun, Hilda and Zara had 1404 erasers. Hilda won some of the erasers from Shiyun and as a result, Hilda's erasers increased by 25%. Zara then won some erasers from Hilda and Zara's erasers increased by 50%. Finally, Zara lost some of her erasers to Shiyun and Shiyun's erasers increased by 20%. In the end, they realised that they each had an equal number of erasers. How many percent less did Shiyun have in the end than what she had at first? Correct your answer to 1 decimal place.

Shiyun	Hilda	Zara
1404
	4 u
- 1 u	+ 1 u
	5 u
		2 p
	- 1 p	+ 1 p
		3 p
5 boxes
+ 1 box		- 1 box
6 boxes
1 group	1 group	1 group

25% = ²⁵₁₀₀ = ¹₄
50% = ⁵⁰₁₀₀ = ¹₂
20% = ²⁰₁₀₀ = ¹₅

Working backwards.

3 groups = 1404

1 group = 1404 ÷ 3 = 468

1 group = 6 boxes
6 boxes = 468

1 box = 468 ÷ 6 = 78

1 group + 1 box = 3 p
468 + 78 = 3 p
3 p = 546

1 p = 546 ÷ 3 = 182

1 p = 1 x 182 = 182

1 group + 1 p = 5 u
468 + 182 = 5 u
5 u = 650

1 u = 650 ÷ 5 = 130

Number of erasers that Shiyun had at first
= 5 boxes + 1 u
= (5 x 78) + 130
= 390 + 130
= 520

Percent that Shiyun had less in the end than at first
= ^{520 - 468}₅₂₀ x 100%
≈ 10.0%

Answer(s): 10.0%