Question

Hi can you guys help me know how to explain this?

Greg knows that 10 x 25 = 250. When the teacher asks the class to multiply 20 x 25, Greg uses mental math to get the correct answer, which is 500. Explain how Greg probably used his knowledge of 10 x 25 = 250 to mentally solve 20 x 25.

Will upvote if helpful :3

Answer 1

10 x 25 = 250, well 20 x 25 is just double that, its 10 doubled x 25 so he probably just added it up. repeated addition really helps with times tables.