Take it one step at a time. First solve for how many white blood cells.
10 to the third power equals 1000. 7 times 1000=7000.
You then want to multiply 7000 by 6 times 10 to second power. 10 to the second power equals 100, and 100 times 6 equals 600. 600 times 7000 equals 4200000. Does this make sense? Correct me if I'm wrong.
