Answer:
10 cm
Explanation:
This is the Pythagorean triple 3, 4, 5, in which the two legs are multiples of 3 and 4, while the hypotenuse is a multiple of 5. Observing the given numbers it can be deduced that the second multiple of 5 is what is needed to complete this triple, therefor the hypotenuse must be 10 cm.