Out of 5.5 billion bacteria grown for an experiment, 1 in 75 million

Question

Out of 5.5 billion bacteria grown for an experiment, 1 in 75 million has a particular mutation. Approximately how many of the bacteria have the mutation?

(A) 7
(B) 73
(C) 733
(D) 7,333
(E) 73,333

doomedcat · Answer

we just need to find how many 75 million (1million =  10^6 ) make 5.5 billion (1billion =  10^9 )

\frac{5.5*10^9}{75*10^6}  
~73
Ans B

dhruvin917 · Answer

I did it the long way:

5,500,000,000 * (1/75,000,000) --> 5,500 * (1/75) --> (5,500/75) --> (1100/15) --> (220/3) --> 73.~

So the answer is B

sk1007 · Answer

B

5.5bn = 5500m

75m has 1 mutation
5500m has 5500/75 = 73.33

LordStark · Answer

1 billion = 1000 million
5.5 billion = 5500 million 
 \frac{5500}{75}  = 73.333

therefore answer is 73 option  B

Abhishek009 · Answer

75  million has  1  bacterial mutation
 1  million has  \frac{1}{75}  bacterial mutations
 5500  million has  \frac{1}{75}*5500  bacteria  ~   73  bacterial mutations ,   Answer must be (B)

PKN · Answer

Total no of bacteria having mutation=Total no of bacteria* rate of mutation=5.5 billion* \frac{1 nos}{75 million} = \frac{5.5*1000 million}{75million} =73(Approx.)
Ans. (B)

EgmatQuantExpert · Answer

Solution 
  Given:  
 • Total number of bacteria grown for an experiment = 5.5 billion
• 1 in every 75 million bacteria has a particular mutation

To find:  
 • Approximately, how many of these 5.5 billion bacteria has the mutation

Approach and Working:   
 • In 75 million bacteria, there is 1 bacteria with the mutation
• In 5.5 billion bacteria grown for the experiment, number of bacteria which have the mutation = 1 * 5.5 billion/75 million = (5.5 *  10^9 )/(75 *  10^6 ) = 5500/75
• The value is greater than 10 and less than 100

Hence, the correct answer is option B.

Answer: B

NandishSS · Answer

HI Bunuel , Is OA E? Can you please correct it?

Bunuel · Answer

The OA is B. Edited. Thank you.

ScottTargetTestPrep · Answer

We can create the proportion:

5,500,000,000/n = 75,000,000/1

n = 5,500,000,000/75,000,000 = 5500/75 = about 73

Answer: B

vaibhav1221 · Answer

2^0  in 75 million
 2^1  in 150 million (number of bacteria with a mutation doubles every time the sample is doubled i.e 75-150-300-..)
 2^2  in 300 million
 2^3  in 600 million
 2^4  in 1200 million
 2^5  in 2400 million
 2^6  in 4800 million;  2^6 = 64 
 2^7  in 9600 million; 2^7 = 128

An option between 64 and 128. Answer is B, 73.

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Out of 5.5 billion bacteria grown for an experiment, 1 in 75 million

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Out of 5.5 billion bacteria grown for an experiment, 1 in 75 million

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