Brandon, Ian and Calvin collected marbles in the ratio of 11 : 5 : 5. After Calvin gave ¹₄ to Brandon and Ian, Calvin had 310 less marbles than Brandon. The number of marbles that Ian had increased by 15%. How many marbles did Brandon and Calvin have in the end?

	Brandon	Ian	Calvin
Before	11 u	5 u	5 u
Change	+ 0.5 u	+ 0.75 u	- 1.25 u
After	11.5 u	5.75 u	3.75 u

Number of marbles that Calvin gave to Brandon and Ian
= ¹₄ x 5 u
= 1.25 u

Number of marbles that Ian received from Calvin
= ¹⁵₁₀₀ x 5 u
= 0.75 u

Number of marbles that Brandon received from Calvin
= 1.25 u - 0.75 u
= 0.5 u

Number of less marbles that Calvin had less than Brandon
= 11.5 u - 3.75 u 
= 7.75 u

7.75 u = 310

1 u = 310 ÷ 7.75 = 40

Number of marbles that Brandon and Calvin had
= 11.5 u + 3.75 u
= 15.25 u
= 15.25 x 40
= 610

Answer(s): 610