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
aev [14]
3 years ago
11

An instructor gives a class a set of 10 problems and says that the nal exam will consist of a random selection of 5 of the probl

ems. If a student has gured out how to solve 7 of the problems, what is the probability that he or she will answer at least 4 problems correctly?
Mathematics
1 answer:
sweet-ann [11.9K]3 years ago
8 0

Answer:

probability that he or she will answer at least 4 problems correctly = 0.5

Step-by-step explanation:

probability that he or she will answer at least 4 problems correctly is given as;

P (at least 4 correctly) = P (exactly 4 correctly) + P (all 5 correctly)

Since there are 10 problems. 4 is from the 7 problems chosen and 1 is from the 3 problems we can't figure out. Thus, P(exactly 4 correctly) = 7C4 x 3C1

Thus, P (at least 4 correctly) = [ (7C4) x (3C1) ] / (10C5)] + [(7C5)/(10C5)]

= [(35 x3)/252 ] + [21/252]

= [ 105/252 ] + [ 21/252 ]

= 126 / 252

= 0.5

You might be interested in
Given QT = SR, QV = SU, and the diagram, prove that triangles QUT and SVR are congruent. Write a paragraph proof.
QveST [7]

Answer:

Triangles QUT and SVR are congruent because the defining two sides and an included angle of triangles QUT and SVR are equal

Step-by-step explanation:

Here we have QT = SR and

QV = SU

Therefore,

QT = √(UT² + QU²)........(1)

RS = √(VS² + RV²)..........(2)

Since QS = QU + SU = QV + VS ∴ QU = VS

Therefore, since SR = QT and QU = VS, then from (1) and (2), we have UT = RV

Hence since we know all sides of the triangles QUT and SVR are equal and we know that the angle in between two congruent sides of the the triangles QUT and SVR that is the angle in between sides QU and UT for triangle QUT and the angle in between the sides RV and VS in triangle SVR are both equal to 90°, therefore triangles QUT and SVR are congruent.

5 0
3 years ago
can some one plz answer my qwestion it is peter weighs 105 kg he want to lose 500 grams per week how many weeks willit take for
svet-max [94.6K]

Answer:

Your answer is he’s going to die out of Obesity

Step-by-step explanation:

8 0
3 years ago
A triangle has an area of 72 square inches. If the base of the triangle has a length of 18 inches, what is the height of the tri
Alecsey [184]
It could be 8 since 8x18= 144 and 144 divided by 2 is 72
8 0
3 years ago
Please help me with this
sesenic [268]
Ok so the average is 50

average of x number of things is
(add value of all things)/x=average

4 test scores needed
so divide by 4
3 test scores ar known
average is 50
x= missing score

(43+48+42+x)/4=50
times 4 both sides
133+x=200
minus 133 both sides
x=67

a score of 67 is needed
5 0
3 years ago
I’m taking a test right now and I had to rush so I wasn’t able to study please help..
Yakvenalex [24]

Answer:

86.13 I think? I scrath it I think its correct

7 0
3 years ago
Read 2 more answers
Other questions:
  • An airplane covers 94 miles in 1/6 of n hour. The plane can cover how many miles in 6 hours
    14·2 answers
  • Find an explicit formula for the arithmetic sequence 170, 85, 0, -85
    6·2 answers
  • PLEASE HELP SUPER EASY 10 POINTS DUE TOMARROW
    13·1 answer
  • What is 3.01 and 2/3 as a decimal
    11·2 answers
  • A)clara believes the sequence 3,9,27,81,243 is arithmetic. Do you agree with clara?Explain your reasoning.
    10·1 answer
  • Square root of 9 on a graph
    5·1 answer
  • Someone please help meee
    14·1 answer
  • use the graph of y=e^x to evaluate the expression e^0. round the solution to the nearest tenth if necessary​
    15·1 answer
  • 2:21:27 PM what is this in non military time
    13·2 answers
  • 33)
    5·2 answers
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!