The missing number in the following table is : 1 7 9 2 14

The missing number in the following table is :

1 7 9
2 14 ?
3 105 117
12
16
26
20
This question was previously asked in
UPSC CAPF – 2009
The correct option is D.
Let the numbers in the table be $C_1, C_2, C_3$ for columns and $R_1, R_2, R_3$ for rows.
The table values are:
$R_1: C_1=1, C_2=7, C_3=9$
$R_2: C_1=2, C_2=14, C_3=?$
$R_3: C_1=3, C_2=105, C_3=117$

Let’s look for a relationship between the columns within each row.
Observe $R_1$: $1, 7, 9$. $1^2 + 7 + 1 = 1 + 7 + 1 = 9$. So $C_1^2 + C_2 + C_1 = C_3$.
Observe $R_3$: $3, 105, 117$. Let’s test the same relationship: $3^2 + 105 + 3 = 9 + 105 + 3 = 117$. This relationship holds for R3 as well.
Let’s apply this relationship to $R_2$: $C_1=2, C_2=14$.
The missing number ($C_3$) should be $C_1^2 + C_2 + C_1 = 2^2 + 14 + 2 = 4 + 14 + 2 = 20$.

Matrix or table-based reasoning problems often involve arithmetic operations, sequences, or functional relationships between the numbers in rows or columns. Identifying the pattern from the given rows is crucial.