1answer.
Ask question
Login Signup
Ask question
All categories
  • English
  • Mathematics
  • Social Studies
  • Business
  • History
  • Health
  • Geography
  • Biology
  • Physics
  • Chemistry
  • Computers and Technology
  • Arts
  • World Languages
  • Spanish
  • French
  • German
  • Advanced Placement (AP)
  • SAT
  • Medicine
  • Law
  • Engineering
Len [333]
3 years ago
12

A maintenance man has 12 keys on his key ring. if he tries the keys at random on a storage room door, discarding those that do n

ot work, what is the probability that he will get the door open on his 4th try?
Mathematics
1 answer:
posledela3 years ago
4 0
P(Failure on first try) = 11/12
P(Failure on second try) = 10/11
P(Failure on third try)= 9/10
P(success on fourth try) = 1/9

P(success exactly on fourth try) = 11/12*10/11*9/10*1/9 = 1/12

You might be interested in
What forms of the following equation in?<br><br> y=5x−3
alexdok [17]
5x-y=3
Not sure if it’s correct
4 0
3 years ago
Read 2 more answers
Plz show work and solve quick please need help!!!!!
Simora [160]
Surface area is just the area of all these 4 triangles plus the rectangle.

First we can find the area of the rectangle.

\sf A=lw

Half of the length is 28 cm, so the full length must be 28 * 2 = 56 cm.

\sf A=(56)(27)

\sf A=1512cm^2

The base for the left and right triangles are 27. The heights would be the net length minus half the length of the rectangle:

\sf 82.8-28=54.8\? cm

Calculate the area:

\sf A=\dfrac{1}{2}bh

\sf A=\dfrac{1}{2}(27)(54.8)

\sf A=739.8\?cm^2

We have two of these triangles.

\sf 739.8\times 2=1479.6\? cm^2

Now do the other two pair of triangles. The bases for them are 28 + 28 = 56 cm. The heights would be the net width minus the width of the rectangle:

\sf 81.2-27=54.2\?cm

Now find the area:

\sf A=\dfrac{1}{2}bh

\sf A=\dfrac{1}{2}(56)(54.2)

\sf A=1517.6\? cm^2

We have two of these triangles.

\sf 1517.6\times 2=3035.2\?cm^2

Add all the areas together:

\sf 1512+1479.6+3035.2=\boxed{\sf 6026.80\? cm^2}
7 0
3 years ago
Combine like terms.<br> - 2x - 14 = -3.- 1
UNO [17]

Answer:

combine -3-1

- 2x - 14 =  - 4

if you want to solve for x then you would move the -14 to the left buy adding 14 to both sides.

- 2x - 14 =  - 4 \\    \:  \:  \:  \:  \:  \:  \:  \:  \:  \:  \:  + 14 \:  \:  + 14

your equation there will be

- 2x = 10

then you will divide -2 on both sides

\frac{ - 2x}{ - 2}  =  \frac{10}{ - 2}

finally x will equal

x =  - 5

3 0
3 years ago
How do i rewrite y=8 (x - 5) (x +2) in standard form
Komok [63]

Answer:

Its already in standard form. LoL

Step-by-step explanation:

y=(x−5)(x+2)

6 0
3 years ago
Convert 18 1/10 into a decimal.
Elodia [21]

Answer:

the answer is 18.1 1/10 is the same thing as .1

6 0
3 years ago
Other questions:
  • A. Solve the differential equation <img src="https://tex.z-dn.net/?f=y%27%3D2x%20%5Csqrt%7B1-y%5E2%7D%20" id="TexFormula1" title
    15·1 answer
  • Find three consecutive integers whose sum is six times the greater integer
    11·1 answer
  • What is 1,200/2,000 in a fraction
    5·1 answer
  • An arc of length 15ft subtends a central angle 0 in a circle of radios 9ft. Find measure of 0 in degrees
    14·1 answer
  • A) Work out the size of angle x.
    13·1 answer
  • A resort hotel has 270 guests. On one​ day, 6 groups of 11 guests leave to shop and 2 groups of 9 guests go sightseeing. Evaluat
    15·1 answer
  • The total cost for skating at the Frenchtown Roller Rink depends on the number of hours a person skates. The roller rink charges
    9·1 answer
  • Easton is a high school basketball player. In a particular game, he made two points and some three point shots.
    7·1 answer
  • Maggie has a bank account balance of -18.37 as soon as she realizes this she deposits 24.50 in the account
    13·1 answer
  • Suppose account numbers for an internet service provider consist of alpha-numeric characters. The first character is a digit (0
    15·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!