Question

Two objects A and B are of lengths 5 cm and 7 cm determined with errors 0.1 cm and 0.2 cm respectively. The error in determining the total length in cm when their lengths are added or subtracted is :

• A. $0.1$
• B. $0.2$
• C. $0.3$
• D. $0.4$

Answer 1

The correct option is C $0.3$

Errors always add be it addition or subtraction.
Addition $=5+7=12$
Error $=0.1+0.2=0.3$
Subtraction $=7-5=2$
Error $=0.1+0.2=0.3$