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You pick a card at random without putting the 1st card back you pick a second card at random what is the probability of picking a 7 and then picking a 7

You pick a card at random without putting the 1st card back you pick a second card-example-1
User Antenka
by
3.1k points

1 Answer

26 votes
26 votes

Given:

There are four cards numbered as


6,\text{ }7,\text{ }8,\text{ and }9.

Required:

We have to find the probability of picking a 7 and then picking a 7.

Step-by-step explanation:

When you pick the first card there are four possibilities out of which only one card is numbered as 7.

Therefore, the probability of picking a 7 is


(1)/(4)

Before picking the second card you have put back the first card. So when you pick the second card there are four possibilities out of which only one card is numbered as 7.

Therefore, the probability of picking a 7 is


(1)/(4)

Hence the probability of picking a 7 and then picking a 7 is


(1)/(4)*(1)/(4)=(1)/(16)

Final answer:

Hence the final answer is


(1)/(16)

User Andy Zarzycki
by
3.2k points
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