Nick, Dylan and Clifford collected buttons in the ratio of 12 : 9 : 7. After Clifford gave ³₄ to Nick and Dylan, Clifford had 247 less buttons than Nick. The number of buttons that Dylan had increased by 35%. How many buttons did Nick and Clifford have in the end?

	Nick	Dylan	Clifford
Before	12 u	9 u	7 u
Change	+ 2.1 u	+ 3.15 u	- 5.25 u
After	14.1 u	12.15 u	1.75 u

Number of buttons that Clifford gave to Nick and Dylan
= ³₄ x 7 u
= 5.25 u

Number of buttons that Dylan received from Clifford
= ³⁵₁₀₀ x 9 u
= 3.15 u

Number of buttons that Nick received from Clifford
= 5.25 u - 3.15 u
= 2.1 u

Number of less buttons that Clifford had less than Nick
= 14.1 u - 1.75 u 
= 12.35 u

12.35 u = 247

1 u = 247 ÷ 12.35 = 20

Number of buttons that Nick and Clifford had
= 14.1 u + 1.75 u
= 15.85 u
= 15.85 x 20
= 317

Answer(s): 317