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brilliants [131]
3 years ago
11

A super has a key ring with 12 keys. He has forgotten which one opens the apartment he needs to enter. What is the probability h

e is able to enter before reaching the 4th key?
Mathematics
1 answer:
svet-max [94.6K]3 years ago
5 0

Answer:

Therefore, the probability is P=1/4.

Step-by-step explanation:

We know that a super has a key ring with 12 keys. He has forgotten which one opens the apartment he needs to enter.

We conclude that each key has an equal probability of opening an apartment. Since there are 12 keys, it follows that the probability for each key is equal,

p = 1/12.

We calculate the probability he is able to enter before reaching the 4th key. So he will try three keys by then. We get:

P=p+p+p\\\\P=\frac{1}{12}+\frac{1}{12}+\frac{1}{12}\\\\P=\frac{3}{12}\\\\P=\frac{1}{4}

Therefore, the probability is P=1/4.

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The perimeter of a square is 20 feet. How long is each side?
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Answer:

5ft

Step-by-step explanation:

all sides of a square are equal and there are 4 sides so divide 20 by 4 and you get 5 ft

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3 years ago
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Valentin [98]
<h3>Answer:  19</h3>

==============================================================

Explanation:

T is the midpoint of PQ, which means T splits PQ into two equal parts. Those parts being PT and TQ.

Set them equal to each other and solve for x.

PT = TQ

3x+7 = 7x-9

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So,

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Both PT and TQ are 19 units long to help confirm the answer.

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m=0 (m is the slope)

Step-by-step explanation:

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m=6-6/1-5

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vlabodo [156]

Answer:

<u>36</u>

Step-by-step explanation:

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CAN SOMEONE PLEASE HELP ME !
77julia77 [94]
I believe the answer would be 24 square units
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