Concept:
Observe the pattern in groups of three.
Step 1:Group the series:
\[
(3, 5, 35), \quad (10, 12, 35), \quad (__, __)
\]
Step 2:Identify pattern in each group:
\[
3 \times 5 + 20 = 35
\]
\[
10 \times 12 + (-85) \text{ (not consistent)}
\]
Instead, observe another pattern:
First two numbers increase by:
\[
3 \rightarrow 10 \rightarrow 19 \quad (+7, +9)
\]
\[
5 \rightarrow 12 \rightarrow ? \quad (+7, +7)
\]
So:
\[
12 + 7 = 19
\]
Step 3:Notice repetition:
\[
35 \text{ appears after every pair}
\]
Step 4:Complete the series:
\[
3, 5, 35, 10, 12, 35, 19, 35
\]
Step 5:Final Answer:
\[
(19, 35)
\]