A chain of designated length 20m is found to be 0.1m too short. Calculate the correct distance when the chain is used to measure a distance of 120m.

• Measured distance ($L_m$) = $120 \text{ m}$
• Designated length of the chain ($L$) = $20 \text{ m}$
• Error in chain length = $0.1 \text{ m}$ too short

Since the chain is $0.1 \text{ m}$ too short, its actual length is:

The formula for the corrected distance ($L_c$) is:

The correct distance between the two points is: