To do this, first divide 85 by 10
You get 8.5
Then, divide 391 by 8.5
You get 46
Therefore, 46 students are left-handed in Tom's school.
Hope this helped!
If you move the decimal point the same number of places in the dividend and the divisor, you are multiplying them both by the same power of 10. That does not change the quotient.
