Find the decimal for: 34/85

Julian wrote the following numeric pattern on the board3,10,17,24,31,38.what numbers of julian's pattern are compound numbers.

Erik buys 2.5 pounds of cashews. if each pound of cashews costs $7.70, how much will he pay for the cashews?

Ineed to know the ordered pairs for this equation i need the answer quick because it’s a timed test