A doctor prescribed 18 cubic centimeters of a certain drug to a patien

Question

A doctor prescribed 18 cubic centimeters of a certain drug to a patient whose body weight was 120 pounds. If the typical dosage is 2 cubic centimeters per 15 pounds of body weight, by what percent should the prescribed dosage be reduced to bring it down to the typical dosage?

(A) 7.5
(B) 9.0
(C) 11.1
(D) 12.5
(E) 14.8

(A) 7.5
(B) 9.0
(C) 11.1
(D) 12.5
(E) 14.8

elegantm · Answer

Idea dosage for 120 pound weight = 120 * 2/15 = 16 cc
Dosage recommended earlier = 18 cc
Reduction = 2cc

Kindly note that 2cc need to be removed from 18 cc and not 16 cc 
Reduction = 2/18 = 1/9

Answer C

sashiim20 · Answer

Typical dosage is  2  cubic centimeters per  15  pounds  = \frac{2}{15}

Let the typical dosage be  x  cubic centimeters for  120  pounds  = \frac{x}{120}

\frac{2}{15} =\frac{x}{120}

x = \frac{2*120}{15} = 16

Therefore typical dosage for  120  pounds is  16  cubic centimeters.

Doctor prescribed  18  cubic centimeters for  120  pounds.

Difference  = 18 - 16 = 2

We need to find the difference ie;  2  is what percentage of the dosage doctor has prescribed  18 .

Required percent  = \frac{2}{18} * 100 = 11.1  .  Answer (C)...

pushpitkc · Answer

Given data : 
Doctor prescribes 18cc for 120pounds body weight  (18:120 = 3:20) 
Ideal dosage is 2cc : 15pounds.

3:20 is nothing but  3*\frac{3}{4} : 20*\frac{3}{4}  = 2.25cc : 15 pounds

So the dosage(2.25cc) must be reduced by .25cc to bring it down to 2cc,

making percent change :  \frac{.25cc}{2.25cc}= \frac{1}{9}  =  11.11%(Option C)

Abhishek009 · Answer

So, 1 pound requires  \frac{2}{15}  cc
Or, 120 pound requires  \frac{2}{15}*180  cc =  16  cc

The doc gave 18 cc, and the patient needs 16 cc

Thus, the doc must reduce dosage by 2 cc

So, the percentage reduction required is  \frac{2}{18} *100= 11.11  %

Hence, the correct answer must be (C) 11.11 %

ydmuley · Answer

A doctor prescribed 18 cubic centimeters of a certain drug to a patient whose body weight was 120 pounds. If the typical dosage is 2 cubic centimeters per 15 pounds of body weight, by what percent should the prescribed dosage be reduced to bring it down to the typical dosage?

(A) 7.5
(B) 9.0
(C) 11.1
(D) 12.5
(E) 14.8

18 cubic centimeters =====> 120 pounds

Typical Dosage = 2 cubic centimeters =====> 15 pounds

120 Pounds Typical dosage  = \frac{120}{15} * 2

= 8 * 2

= 16

Total dosage administered  = 18

Additional dosage  = 18 - 16   = 2

What % should be reduced?  = \frac{2}{18} * 100 = 100/9 = 11.1

Hence, Answer is C

ScottTargetTestPrep · Answer

We are given that the typical rate is (2 cm^3)/(15 lbs). Thus a patient whose weight was 120 lbs should be prescribed 120 lbs x (2 cm^3)/(15 lbs) = 240/15 = 16 cm^3 of the drug. 
 
However, since a doctor prescribed 18 cm^3 of the drug, we can let n = the percentage decrease needed and create the following equation: 
 
18(1 - n/100) = 16
 
1 - n/100 = 16/18
 
2/18 = n/100
 
18n = 200
 
n = 11.11
 
Answer: C

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A doctor prescribed 18 cubic centimeters of a certain drug to a patien

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