Rael had some strawberry biscuits and chocolate chip biscuits. ³₄ of the number of strawberry biscuits was equal to ¹₅ of the number of chocolate chip biscuits. After Rael made 5 more strawberry biscuits, the number of strawberry biscuits was ¹₃ of the number of chocolate chip biscuits. How many biscuits did he have altogether in the end?
Make the numerators the same. LCM of 3 and 1 is 3.

34 of strawberry biscuits = 1x35x3 of chocolate chip biscuits

³₄ of strawberry biscuits = ³₁₅ of chocolate chip biscuits

	Strawberry biscuits	Chocolate chip biscuits	Total
Before	4 u	15 u
Change	+ 5
After	1x5 = 5 u	3x5 = 15 u	20 u

The number of chocolate chip biscuits remains unchanged.  Make the number of chocolate chip biscuits the same.  LCM of 3 and 15 is 15.

Number of more strawberry biscuits made
= 5 u - 4 u
= 1 u

1 u = 5

1 u = 5 ÷ 1 = 5

Number of biscuits that Rael had in the end
= 5 u + 15 u
= 20 u
= 20 x 5
= 100

Answer(s): 100