Mike changes tires on different vehicles.  He changes all the tires on 12 motorcycles and all the tires on 10 cars.  How many tires did he change?
He changed 12*2=<<12*2=24>>24 motorcycle tires
He changed 10*4=<<10*4=40>>40 car tires
So he changed 24+40=<<24+40=64>>64 total tires
#### 64