At a local gym, 10 of the 40 trainers currently have CPR certification. Next year, the gym plans to have 46 trainers, and the ow
ner wants the percentage of trainers with CPR certification to remain the same. The owner uses the following calculations to determine that 6 additional trainers will need CPR certification. Step 1: 10 ÷ 40 = 0.25
Step 2: 0.25 x 100 = 25%
Step 3: 46 – 40 = 6 trainers
What is the first error that the owner makes?
a. In Step 3, the owner should have subtracted 46 – 25%.
b. In Step 3, the owner should have found 25% of 46 by multiplying 0.25 x 46.
c. In Step 1, the owner should have divided 40 by 10. This affects the resulting percentage and the calculation of the number of additional trainers needing certification.
d. In Step 1, the owner should have divided 10 by 46. This affects the resulting percentage and the calculation of the number of additional trainers needing certification.
e. In Step 2, the owner calculated the percentage incorrectly. The correct percentage is 2.5%. This affects the calculation of the number of additional trainers needing certification.
Set up a proportion to solve. (4mg/5ml)= (20mg/x ml) Be sure you line up the mg to mg and the ml to ml. Notice I have both mg on the numerator and both ml on the denominator. To solve you need to cross multiply. 4x = 5(20) 4x = 100 divide by 4 x = 25 ml
