An integer between 1 and 10 inclusive is selected at random. Given tha

Question

An integer between 1 and 10 inclusive is selected at random. Given that the integer selected is odd, what is the probability that it is a multiple of 3?
  
A. 3/10
B. 2/10
C. 3/5
D. 2/5
E. 1/5

gmatophobia · Answer

Between 1 and 10, there are 5 odd integers, and only 2 are multiple of 3.

Hence probability = 2/5

P.S. - Option B and Option E represent the same value.

BahaaMadi · Answer

I dont know if its just me or if this is actually poorly worded, what I can understand from this is that given the selected integer is odd so 3 or 9

GMATCoachBen · Answer

BahaaMadi

This kind of wording is valid and appears on official questions.

You're correct: 3 or 9 are the 2 possible options that fit our criteria of odd multiples of 3.

So, our numerator is 2.

For the denominator: since the question says "Given that the integer selected is odd," the total number of options we're picking from only includes odd numbers: 1, 3, 5, 7, 9.

So, our denominator is 5.

Our answer is    2/5.

luisdicampo · Answer

Deconstructing the Question  
An integer from 1 to 10 is selected.
Given that the number is  odd , we only consider the odd numbers.

So we want:
 P(	ext{multiple of 3 | odd})

Step-by-step  
Odd numbers between 1 and 10:
 \{1,3,5,7,9\} 
Total =  5

Multiples of 3 among them:
 \{3,9\} 
Total =  2

Therefore:
 \frac{2}{5}

Answer:     (D) 2/5

An integer between 1 and 10 inclusive is selected at random. Given tha

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An integer between 1 and 10 inclusive is selected at random. Given tha

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