If in a certain code language, AIR is written as 31120, then how will GAS be coded in that language?

9321

The correct answer is Option (4) → 9321

1. Analyze the Code for "AIR"

First, identify the numerical position of each letter in the English alphabet ($A=1, B=2, \dots$):

• A = 1
• I = 9
• R = 18

Now, compare these positions to the code 31120:

• For A (1): $1 + 2 = \mathbf{3}$
• For I (9): $9 + 2 = \mathbf{11}$
• For R (18): $18 + 2 = \mathbf{20}$

When you concatenate these results ($3, 11, 20$), you get 31120.

2. Apply the Logic to "GAS"

Follow the same steps for the word GAS:

• G = 7th letter
• A = 1st letter
• S = 19th letter

Apply the "$+2$" rule to each position:

• For G (7): $7 + 2 = \mathbf{9}$
• For A (1): $1 + 2 = \mathbf{3}$
• For S (19): $19 + 2 = \mathbf{21}$

Concatenating these results ($9, 3, 21$) gives the code 9321.

Conclusion

The code for GAS is 9321.