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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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Relate a vertical line test to understanding functions.
xenn [34]

Answer:

c.

Each vertical line drawn through the graph will intersect a relation in only one location

Step-by-step explanation:

We know that a vertical line test is done to test whether the graph or the given relation  is a function or not and it  states that:

Each vertical line parallel to the co-domain drawn on a graph will intersect the graph exactly once.

i.e. there is a unique image of each pre-image.

Hence, option: C is the correct answer.

c.

Each vertical line drawn through the graph will intersect a relation in only one location.

6 0
3 years ago
Kamal solved an equation as shown below. 3(x-8)=x+2x+7 3x-24=3x+7 -24=7 What is the solution to Kamal’s equation?
dem82 [27]

Answer:

7 is correct

Step-by-step explanation:

7 0
3 years ago
Read 2 more answers
The scale of a map is 0.5 inch: 50 miles. on the map, the distance between two cities is 5 inches. what is that actual distance
Kipish [7]
.5 inch / 50 miles = 5 inches / x miles
x = 500 miles
4 0
2 years ago
4x+y=8 and x+3y=8 graphed
IRISSAK [1]
standard \ linear \ equation\ :\\\\y=ax+b\\\\ \begin{cases} 4x+y=8\ \ |\ subtract\ 4x\ to\ both\ sides\\ x+3y=8 \ \ |\ subtract\ x\ to\ both\ sides \end{cases}\\\\\begin{cases} y=-4x+8 \\ 3y=-x+8\ \ | \ divide \ each \ term \ by \ 3 \end{cases}

\begin{cases} y=-4x+8 \\ y=-\frac{1}{3}x+\frac{8}{3} \end{cases}\\\\y=-4x+8\\ To \ find \ the \ x-axis \ intersection \ point, \\set \ y \ equal \ to \ zero \ and \ solve \ for \ x : \\ \\y=0 \ \to 0=-4x+8\\\\4x=8 \ \ | \ divide \ both \ sides\ by\ 4 \\\\x=2\\\\ point : \ \ (2,0)
 
To \ find \ the \ y-axis \ intersection \ point, \\set \ x \ equal \ to \ zero \ and \ solve \ for \ y : \\ \\x=0 \ \to y=-4 \cdot 0+8\\ y=8 \\ point: \ \ (0,8)


y=-\frac{1}{3}x+\frac{8}{3}\\\\ \ the \ x-axis \ intersection \ point \\ \\y=0 \ \to 0=-\frac{1}{3}x+\frac{8}{3}\\ \frac{1}{3}x=\frac{8}{3} \ \ | \ multiply\ both\ sides\ by\ 3 \\\\x=8 \\\\point: \ \ (8,0)

the \ y-axis \ intersection \ point \\ \\x=0 \ \to y=-\frac{1}{3} \cdot 0+\frac{8}{3} \\ y=\frac{8}{3} \\ point : \ \ (0,\frac{8}{3})


Answer :\\\\ \begin{cases} y=-4x+8 \ \ | \ multiply \ each \ term \ by \ (-3) \\ 3y=-x+8 \end{cases}\\\begin{cases} -3y=12x-24 \\ 3y=-x+8 \end{cases}\\+-------\\0=11x-16\\11x=16\ \ | \ divide \ both \ sides\ by\ 11\\x=\frac{16}{11}

y=-4 \cdot \frac{16}{11}+8 \\ y=- \frac{ 64}{11}+\frac{88}{11}\\y= \frac{24}{11}\\\\\begin{cases} x=\frac{16}{11} \\ y=\frac{24}{11} \end{cases}


3 0
3 years ago
50% of a number is 32 <br> what is the number
Paladinen [302]

Answer:

64

Step-by-step explanation:

Half (50%) of 64 would be 32

6 0
3 years ago
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