Complete: 3, 6, 9, __.

**The reasoning** This is a **number pattern** (also called a sequence). Look at what's happening between the numbers: - From 3 to 6: we add 3 - From 6 to 9: we add 3 again The pattern is clear: **add 3 each time** (or count in multiples of 3). So: 3, 6, 9, **12** You can also think of it as the **3 times table**: 3×1, 3×2, 3×3, 3×4 = 12. **Why the wrong options tempt you** - **10 & 11**: These come from just counting forward (9, 10, 11...), ignoring the actual pattern. That's the trap — you're rushing and not checking *how* the numbers increase. - **15**: This jumps too far. You might pick it if you saw "multiples of 3" but skipped counting properly (3, 6, 9, 15 misses the 12). **Quick takeaway** Always find the **difference between consecutive terms** first — that difference is your key to unlocking any number pattern!