Directions: In the following question there is some relationship between the two terms to the left of : : and the same relationship is between the two terms to its right. One term either to the right of : : or to the left of it is missing. Find the missing term.

DE : 10 : : HI : ?

DE gives 10. D(4) and E(5) are consecutive letters. 4+5=9, but the answer is 10. Maybe it's D×E = 4×5 = 20? No, that's too high. Perhaps (position of first + 1) × (position of second): (4+1)×5 = 25? No. Let me try D(4) + E(5) + 1 = 10. For HI: H(8) + I(9) = 17, but 8+9+1 = 18, not in options. Actually for DE: 4+5+1=10. For HI: 8×9=72, no. 8+9=17 no. (8+1)×9=81 no. 8×(9+1)=80 no. Wait, maybe it's (sum of consecutive integers starting from first letter position)? 4+5=9 but we have 10. 8+9+10+11=38 no. 8+9=17 no. Let me reconsider: D=4, E=5, DE could mean 4×5÷2 = 10 (sum of 4 through 4+1-1 = just 4). No. Actually 4+5=9, maybe they add 1 for some reason. For HI: 8×9÷2 = 36. Yes! The formula is (first letter position × second letter position) ÷ 2 = 4×5÷2 = 10 for DE, and 8×9÷2 = 36 for HI.