A jar contains 5 marbles: 3 red and 2 blue. If two marbles are drawn

Question

A jar contains 5 marbles: 3 red and 2 blue. If two marbles are drawn randomly from the jar, what is the probability that they will be different colors?

A. 3/25

B. 6/25

C. 2/5

D. 3/10

E. 3/5

deepverma · Answer

3c1*2c1/5c2 = 3/5. Answer E

Sent from my Redmi 5 Plus using  GMAT Club Forum mobile app

Salsanousi · Answer

Probability that both are red = 3/5 * 2/4 = 6/20 = 3/10

Probability that both are blue = 2/5 * 1/4 = 2/20 = 1/10

The probability that the marbles are different = 1 - probability the marbles are not different = 1 - (3/10 + 1/10) = 1 - (4/10) = 6/10 = 3/5

Alternatively, the probability they are different = 3/5 * 2/4 = 3/10 here we choose the red first then blue

2/5 * 3/4 = 6/20 = 3/10 here we choose the blue first then the red.

3/10 + 3/10 = 6/10 = 3/5 Answer choice E

Archit3110 · Answer

P red * P blue= (3/5)*(2/4)= 6/20=3/10
P blue * P red= (2/5)* (3/4)= 3/10

3/10+3/10= 6/10=3/5 E

dollytaneja51 · Answer

Prob of getting 1 red marble is 3C1 = 3
Prob of getting 1 blue marble is 2C1 = 2
Prob of getting 2 marbles is 5C2 = 10
Now 3*2/10
= 3/5
E is the answer

Posted from my mobile device

MathRevolution · Answer

Total marbles: 5

Red: 3 
 Blue: 2

Two marbles are drawn randomly from the jar: ^5{C_2} = 10

The probability that they will be different colors: '1' from each = ^3{C_1} * ^2{C_1} = 3 * 2 = 6

Probability:  \frac{6}{10} = \frac{3}{5}

Answer E

MBAHOUSE · Answer

A jar contains 5 marbles: 3 red and 2 blue. If two marbles are drawn randomly from the jar, what is the probability that they will be different colors?

A. 3/25

B. 6/25

C. 2/5

D. 3/10

E. 3/5

bumpbot · Answer

Automated notice from GMAT Club BumpBot: 

A member just gave Kudos to this thread, showing it’s still useful. I’ve bumped it to the top so more people can benefit. Feel free to add your own questions or solutions.

 This post was generated automatically.

A jar contains 5 marbles: 3 red and 2 blue. If two marbles are drawn

Prep Toolkit

Top 5 GMAT Debrief Videos

615 to 715 in 15 Days (Ria's Strategies)

More than Quant/Verbal Abilities: Speed vs. Accuracy

745 with Only Self-Prep and GMAT Club

From 555 to 765: 210-point Improvement

Perfect 805 Score Debrief by Julia

My Rewards

GMAT Problem Solving (PS) Questions

A jar contains 5 marbles: 3 red and 2 blue. If two marbles are drawn

Prep Toolkit

615 to 715 in 15 Days (Ria's Strategies)

More than Quant/Verbal Abilities: Speed vs. Accuracy

745 with Only Self-Prep and GMAT Club

From 555 to 765: 210-point Improvement

Perfect 805 Score Debrief by Julia

My Rewards