Respuesta :

Multiply:  8*63.  You might break up that 63 into two parts:  60 and 3.
Now multiply 8 times 60 and 8 times 3, separately, and then add together the two products:

8*60   =  480
8 * 3    =    24
Sum:       504

This is a good example of mental math, where you use math tricks to do calculations without a calculator.