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

	Silver marbles	Red marbles	Total marbles
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 marbles that were poured into the basket
= 25% x 8 u
= ²⁵₁₀₀ x 8 u
= 2 u

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

Total number of more marbles 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 marbles in the basket at first
= 8 u + 5 u
= 13 u
= 13 x 10
= 130

Answer(s): 130