Victoria made 36 more durian shortbreads than blueberry shortbreads. After she gave away ²₇ of the durian shortbreads and ¹₈ of the blueberry shortbreads, there were an equal number of durian shortbreads and blueberry shortbreads left. How many durian shortbreads did she give away?

	Durian shortbreads	Blueberry shortbreads	Difference
Before	7x7 = 49 u	8x5 = 40 u	9 u
Change	- 2x7 = - 14 u	- 1x5 = - 5 u
After	5x7 = 35 u	7x5 = 35 u

Fraction of durian shortbreads left
= 1 - ²₇
= ⁵₇

Fraction of blueberry shortbreads left
= 1 - ¹₈
= ⁷₈

The number of durian shortbreads and blueberry shortbreads in the end is the same. Make the numerators the same.  LCM of 7 and 5 is 35.

⁵₇ of durian shortbreads = ⁷₈ of blueberry shortbreads
³⁵₄₉ of durian shortbreads = ³⁵₄₀ of blueberry shortbreads

Number of more durian shortbreads than blueberry shortbreads at first
= 49 u - 40 u
= 9 u

9 u = 36

1 u = 36 ÷ 9 = 4

Number of durian shortbreads that Victoria gave away
= 49 u - 35 u
= 14 u
= 14 x 4
= 56

Answer(s): 56