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
Yuri [45]
3 years ago
8

Two methods, A and B, are available for teaching Spanish. There is a 70% chance of successfully learning Spanish if method A is

used, and a 85% chance of success if method B is used. However, method B is substantially more time consuming and is therefore used only 20% of the time (method A is used the other 80% of the time). The following notations are suggested:
A—Method A is used.
B—Method B is used.
L—Spanish was learned successfully. A person learned Spanish successfully.

What is the probability that he was taught by method A?
Mathematics
1 answer:
lara [203]3 years ago
8 0

Answer:

0.7671 = 76.71% probability that he was taught by method A

Step-by-step explanation:

Conditional Probability

We use the conditional probability formula to solve this question. It is

P(B|A) = \frac{P(A \cap B)}{P(A)}

In which

P(B|A) is the probability of event B happening, given that A happened.

P(A \cap B) is the probability of both A and B happening.

P(A) is the probability of A happening.

In this question:

Event A: Person learned Spanish successfully.

Event B: Method A was used.

Probability of a person learning Spanish successfully:

70% of 80%(using method A)

85% of 20%(using method B)

So

P(A) = 0.7*0.8 + 0.85*0.2 = 0.73

Probability of a person learning Spanish successfully and using method A:

70% of 80%, so:

P(A \cap B) = 0.7*0.8 = 0.56

What is the probability that he was taught by method A?

P(B|A) = \frac{P(A \cap B)}{P(A)} = \frac{0.56}{0.73} = 0.7671

0.7671 = 76.71% probability that he was taught by method A

You might be interested in
Rewrite the expression in standard form ( use the fewest number of symbols and characters possiable). a. 5g•7h b.3•4•5•m•n
CaHeK987 [17]

Answer:

a. 35 *gh or 35 gh

b. 60 *mn or 60 mn

Step-by-step explanation:

The fewest number of symbols and characters can be obtained by multiplying the constant numbers with the constant numbers and variables with the variables.

a. The co efficients 5 and 7 are multiplied to get 35 and g is multiplied with h to get gh. So the answer is 35*gh. It can be further simpliefied into 35 gh

b. The co efficients 3,4 and 5 are multiplied to get 60 and m is multiplied with n to get mn. The answer is 60* mn. On further simplificaation we get 60 mn.

6 0
2 years ago
Lori bought a shirt and a hat at half-off sale. If she spent a total of $21 on the two items, what was the original price of the
Rzqust [24]

Answer:

41

Step-by-step explanation:

first you do 21×2 and that's literally it

3 0
2 years ago
Given: AB tangent at D, AD = OD = 4 Find: Area of the shaded region
MrMuchimi

Answer:

1.72

Step-by-step explanation:

AB tangent at D, AD = OD = 4

so triangle OAD is right angle with side of 4 and 4.

area of OAD = 1/2 * 4 * 4 = 8

Angle AOD = DAO = 45 deg.

so circular sector OCD area = area of circle O * 45/360

= pi * 4 * 4 * 45/360

= 2pi

Shade area ACD = trigangle OAD - circular sector OCD

= 8 - 2pi

= 1.72

4 0
3 years ago
Which is smaller -5 or -17
inessss [21]
-5 because it is closest to zero and -17 is farther than zero on a number line :) <span />
8 0
3 years ago
Read 2 more answers
This thing is hard help me please I need to get a good grade
Greeley [361]

Step-by-step explanation:

2y=14

y=7

-2x-2(7)=-28

-2x=-28+14

-2x=-14

x=7

4 0
3 years ago
Other questions:
  • What value of x satisfies the system of equations {2x+5y=35x=−10−15y? Enter your answer as the correct value for x, like this: 4
    10·1 answer
  • List the following stocks and bonds in order from lowest default risk to highest default risk.
    15·1 answer
  • Points points points
    6·2 answers
  • Two right triangles that are not similar still may have one congruent acute angle in common
    8·2 answers
  • A tank starts out with 860 gallons of liquid. A pump adds liquid to the tank at a constant rate. After 8 hours, the tank contain
    15·2 answers
  • I NEED HELP PLEASE :(
    13·1 answer
  • Help me out here pleaseeeeeee
    8·2 answers
  • -4 x f (8) + 3 x g(-7) HELP ASAP
    8·1 answer
  • Remember reality is an illusion the universe is a hologram buy gold bye
    15·2 answers
  • Mr. Strand mowed 2/5 of his lawn. His son mowed 1/4 of it. Who mowed most of the lawn? How much of the lawn still needs to be mo
    7·2 answers
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!