Find the missing number from the below options.
| 16 | 30 | 18 |
| 4 | 34 | ? |
| 10 | 32 | 40 |
Answer & explanation
Correct answer: option 1
The correct answer is Option (1) → 62
The rule runs down the columns: in each column the bottom number is the average of the two numbers above it, so the middle number is twice the bottom number minus the top number.
Column 1: \(\displaystyle\frac{16+4}{2}=10\)
Column 2: \(\displaystyle\frac{30+34}{2}=32\)
Column 3: \(\displaystyle\frac{18+?}{2}=40\), so \(?=80-18=62\)