Question

The length of two sides of a triangle are 10 cm and 12 cm. What can be the length of the third side?

• A. 21 cm
• B. 23 cm
• C. 25 cm
• D. 27 cm

Answer 1

The correct option is A 21 cm

The sum of the lengths of any two sides of a triangle is always greater than the third side.
That is, the third side < (10 + 12) which is 22 cm.
Among the given options, only 21 cm satisfies this condition.
Hence, the measure of the third side is 21 cm.