In a certain code language, 'HUNTER' is coded as 80 and 'TRIAL' is coded as 55. How will 'BURNT' be coded in the same language?

Let's calculate the sum of positional values of the letters for each word:
For HUNTER:

H=8

U=21

N=14

T=20

E=5

R=18

Sum=8+21+14+20+5+18=86
The code is given as 80. Notice that 86−6=80 (where 6 is the number of letters in 'HUNTER').

For TRIAL:

T=20

R=18

I=9

A=1

L=12

Sum=20+18+9+1+12=60
The code is given as 55. Notice that 60−5=55 (where 5 is the number of letters in 'TRIAL').

Logic: Code=(Sum of letter positions)−(Total number of letters)

Now applying this to BURNT:

B=2

U=21

R=18

N=14

T=20

Sum=2+21+18+14+20=75
Number of letters in 'BURNT' = 5.

Code=75−5=70