a pharmacist failed to place the balance in equilibrium before weighing 200mg of a drug. later, he discovered a 20% error was incurred. If the balance pan on which he placed the drug to be measured was heavy, how much of the drug in milligrams did he actually weigh?
200 * 1.2 = 240 mg.
To find out how much of the drug the pharmacist actually weighed, we can use the concept of percentages and the equation:
Actual weight = Measured weight - (Error percentage * Measured weight)
In this case, the measured weight is 200mg and the error percentage is 20% or 0.2. Let's substitute these values into the equation:
Actual weight = 200mg - (0.2 * 200mg)
Multiplying 0.2 by 200mg gives us 40mg:
Actual weight = 200mg - 40mg
Subtracting 40mg from 200mg gives us the actual weight:
Actual weight = 160mg
Therefore, the pharmacist actually weighed 160mg of the drug.
To calculate how much of the drug the pharmacist actually weighed, we need to take into account the 20% error incurred because the balance pan was heavy.
Let's break down the calculation step by step:
1. Start with the weight the pharmacist intended to measure: 200 mg.
2. Calculate the amount of the error incurred due to the balance being heavy:
Error = 200 mg * 20% = 200 mg * 0.20 = 40 mg.
3. Determine the actual weight measured by subtracting the error from the intended weight:
Actual weight measured = Intended weight - Error
= 200 mg - 40 mg
= 160 mg.
Therefore, the pharmacist actually weighed 160 mg of the drug.