Correct Answer - Option 2 : 99 m
Concept:
The actual length of line is measured by;
Correct length = (wrong chain length/Corrcet chain length) × measured length
Correct length (l) × correct chain length (L) = Wrong chain length (L') × meausred length (l')
Calculation:
Given,
L = 20 m, L' = 19.8 m, l' = 100 m
∵ We know that, Correct length (l) × correct chain length (L) = Wrong chain length (L') × meausred length (l')
Correct length (l) × 20 = 19.8 × 100
Correct length = 99 m