Daniel has 10% as many buttons as Zane. If Daniel gives away 25% of the buttons and Zane gives away 80% of his buttons, they will have 132 buttons altogether. How many buttons do the two of them have?

	Daniel	Zane	Total
Comparing Daniel and Zane at first	1x4 = 4 u	10x4 = 40 u
Before	4x1 = 4 u	5x8 =  40 u
Change	- 1x1 = - 1 u	- 4x8 = - 32 u
After	3x1 = 3 u	1x8 = 8 u	132

10% = ¹⁰₁₀₀ = ¹₁₀

25% = ²⁵₁₀₀ = ¹₄ 

80% =⁸⁰₁₀₀ = ⁴₅ 

The number of buttons that Daniel has at first is repeated.  Make the number of buttons that Daniel has the same.  LCM of 1 and 4 is 4 u.

The number of buttons that Zane has at first is repeated. Make the number of buttons that Zane has the same. LCM of 10 and 5 is 40 u.

Number of buttons in the end
= 3 u + 8 u
= 11 u

11 u = 132

1 u = 132 ÷ 11 = 12

Total number of buttons that the two of them have
= 4 u + 40 u
= 44 u
= 44 x 12
= 528

Answer(s): 528