Answer: 0.0189
Step-by-step explanation: Whenever we divide numbers by whole number powers of ten, the number being divided becomes smaller, just as they become larger when we divide by decimal powers of ten.
Using mental math, first, count the number of zeros in the power of ten number. There are two zeros for a hundred (100). Then, move the decimal point in the numerator (1.89) two places to the left.
1.89 → 0.0189
The quotient of 1.89 divided by 100 is 0.0189
In summary, the decimal point is moved to the left once for the number of zeros in the power of ten number. 10 has one zero, so the decimal point is moved one place to the left; 1000 has three zeros and therefore the decimal point is moved three places to the left.
It is also important to note that depending on what type of power of ten the denominator (the divisor) is, one can calculate quotients using mental math.