You pick a card at random, put it back, and then pick another card at random.
5678
What is the probability of picking a 7 and then picking a 6?
Simplify your answer and write it as a fraction or whole number.
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Answer :

To find the probability of picking a 7 and then picking a 6 from a standard deck of playing cards, where you replace the first card before drawing the second card, we need to consider the process step by step. Please note that a standard deck of cards contains 52 cards, with 4 cards for each rank (Ace through King), which means there are 4 sevens and 4 sixes.

First, we calculate the probability of drawing a 7:

1. There are 4 sevens in the deck, and a total of 52 cards. Therefore, the probability of drawing a 7 on your first draw is:

[tex]\( P(\text{7 first}) = \frac{4}{52} \)[/tex]

Simplify this by dividing both the numerator and the denominator by 4 to get:

[tex]\( P(\text{7 first}) = \frac{1}{13} \)[/tex]

Since we are replacing the seven back into the deck, the composition of the deck returns to its initial state of 52 cards.

Next, we calculate the probability of drawing a 6 after having put the 7 back:

2. Similarly, there are 4 sixes in the deck and the total remains 52 cards. Thus, the probability of drawing a 6 after replacing the 7 is:

[tex]\( P(\text{6 second}) = \frac{4}{52} \)[/tex]

Simplify this to get:

[tex]\( P(\text{6 second}) = \frac{1}{13} \)[/tex]

To find the combined probability of both independent events occurring (drawing a 7 first, and then a 6 after replacing the first card), we multiply the probabilities of the two individual events:

[tex]\( P(\text{7 first and 6 second}) = P(\text{7 first}) \times P(\text{6 second}) \)[/tex]

Substitute the simplified probabilities into the equation:

[tex]\( P(\text{7 first and 6 second}) = \frac{1}{13} \times \frac{1}{13} \)[/tex]

Multiply the fractions:

[tex]\( P(\text{7 first and 6 second}) = \frac{1 \times 1}{13 \times 13} \)[/tex]

[tex]\( P(\text{7 first and 6 second}) = \frac{1}{169} \)[/tex]

The probability of picking a 7 and then picking a 6, with replacement, is [tex]\(\frac{1}{169}\)[/tex].

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