Answer:
b < 3071/390
Explanation:
1) Multiply both sides by 100 : 3.9b x 100 + 3.29 x 100 < 34 x 100
2) Refine : 390b + 329 < 3400
3) Subtract 329 from both sides : 390b + 329 - 329 < 3400 - 329
4) Simplify : 390b < 3071
5) Divide both sides by 390 : 390b/390 < 3071/390
6) b < 3071/390