Nick, Ian and Charles collected marbles in the ratio of 9 : 5 : 7. After Charles gave ³₁₀ to Nick and Ian, Charles had 171 less marbles than Nick. The number of marbles that Ian had increased by 10%. How many marbles did Nick and Charles have in the end?

	Nick	Ian	Charles
Before	9 u	5 u	7 u
Change	+ 1.6 u	+ 0.5 u	- 2.1 u
After	10.6 u	5.5 u	4.9 u

Number of marbles that Charles gave to Nick and Ian
= ³₁₀ x 7 u
= 2.1 u

Number of marbles that Ian received from Charles
= ¹⁰₁₀₀ x 5 u
= 0.5 u

Number of marbles that Nick received from Charles
= 2.1 u - 0.5 u
= 1.6 u

Number of less marbles that Charles had less than Nick
= 10.6 u - 4.9 u 
= 5.7 u

5.7 u = 171

1 u = 171 ÷ 5.7 = 30

Number of marbles that Nick and Charles had
= 10.6 u + 4.9 u
= 15.5 u
= 15.5 x 30
= 465

Answer(s): 465