Pharmacy uses primarily the metric system of measure, which is a decimal system. Thus, the majority of the calculations will deal with decimals. At times, it is necessary to change a fraction to a decimal to simplify a procedure
CONVERTING A FRACTION TO A DECIMAL
A. If a decimal is to be multiplied by a number that is a multiple of ten (10, 100, 1000, etc.), move the decimal point as many places to the RIGHT as there are zeros in the multiplier.
A.If a decimal is to be divided by a multiple of ten (10, 100, 1000,etc.), move the decimal point as many places to the left as there are zeroes in the divisor.
When dividing 0.2 by 100, move the decimal point one place to the left for each of the zeros in the divisor (the number you are dividing Into the other number). There are two zeros, therefore, we move the decimal two places to the left.