A basket contained silver and red buttons. There were 60% more silver buttons than red buttons. When 55 more buttons were poured into the basket, the amount of silver buttons increased by 25% and the amount of red buttons increased 70%. How many buttons were in the basket at first?

	Silver buttons	Red buttons	Total buttons
Before	8 u	5 u	13 u
Change	+ 2 u	+ 3.5 u	+ 5.5 u
After	10 u	8.5 u	18.5 u

100% + 60% = 160%

160% = ¹⁶⁰₁₀₀ = ⁸₅

Number of more silver buttons that were poured into the basket
= 25% x 8 u
= ²⁵₁₀₀ x 8 u
= 2 u

Number of more red buttons that were poured into the basket
= 70% x 5 u
= ⁷⁰₁₀₀ x 5 u
= 3.5 u

Total number of more buttons that were poured into the basket
= 2 u + 3.5 u
= 5.5 u

5.5 u = 55

1 u = 55 ÷ 5.5 = 10

Number of buttons in the basket at first
= 8 u + 5 u
= 13 u
= 13 x 10
= 130

Answer(s): 130