Xuan baked 30 biscuits. ³₅ of the biscuits were peach biscuits. The rest were cherry biscuits. She gave an equal number of peach biscuits and cherry biscuits away and had 4 times as many peach biscuits as cherry biscuits left. How many biscuits did she give away?

	Peach biscuits	Cherry biscuits	Difference
Before	3x3 = 9 u	2x3 = 6 u	1x3 = 3 u
Change	- 5 u	- 5 u
After	4x1 = 4 u	1x1 = 1 u	3x1 = 3 u

Since Xuan gave away an equal number of peach biscuits and cherry biscuits, the difference in the number of peach biscuits and cherry biscuits remains unchanged.  Make the difference in the peach biscuits and cherry biscuits the same.  LCM of 1 and 3 is 3.

Total number of biscuits at first
= 9 u + 6 u
= 15 u

15 u = 30

1 u = 30 ÷ 15 = 2

Number of biscuits that Xuan gave away
= 5 u + 5 u
= 10 u
= 10 x 2 
= 20

Answer(s): 20