Glen had some blueberry cookies and strawberry cookies. ²₇ of the number of blueberry cookies was equal to ¹₅ of the number of strawberry cookies. After Glen made 108 more blueberry cookies, the number of blueberry cookies was ⁵₂ of the number of strawberry cookies. How many cookies did he have altogether in the end?
Make the numerators the same. LCM of 2 and 1 is 2.

27 of blueberry cookies = 1x25x2 of strawberry cookies

²₇ of blueberry cookies = ²₁₀ of strawberry cookies

	Blueberry cookies	Strawberry cookies	Total
Before	7 u	10 u
Change	+ 108
After	5x5 = 25 u	2x5 = 10 u	35 u

The number of strawberry cookies remains unchanged.  Make the number of strawberry cookies the same.  LCM of 2 and 10 is 10.

Number of more blueberry cookies made
= 25 u - 7 u
= 18 u

18 u = 108

1 u = 108 ÷ 18 = 6

Number of cookies that Glen had in the end
= 25 u + 10 u
= 35 u
= 35 x 6
= 210

Answer(s): 210