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4 years ago

A student throws 3 coins in the air. Find the probability that exactly 2 landed on heads, given that at least 2 landed on heads.

1 answer:

Nutka1998 [239]4 years ago

7 0

In problems of probability, it is best to find out the sample space or all the possible outcomes from throwing 3 coins in the air.
S = {HHH, TTT, HHT....}

The condition is at least 2 landed on heads (that means 2 or more). From the sample space, that can only be {<span>THH, </span>HHT, HTH, and HHH}.

Therefore, the probability is 3/4 since there are a total of 8 possible outcomes.

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Which of the following is equal to the expression above

EleoNora [17]

Answer:

$15 \sqrt[3]{2}$

Step-by-step explanation:

${(27 \times 250)}^{ \frac{1}{3} } = {(27 \times 125 \times 2)}^{ \frac{1}{3} } \\ = {27}^{ \frac{1}{3} } \times {125}^{ \frac{1}{3} } \times {2}^{ \frac{1}{3} } \\ = \sqrt[ 3]{27} \times \sqrt[3]{125} \times \sqrt[3]{2} \\ = \sqrt[3]{ {3}^{3} } \times \sqrt[3]{ {5}^{3} } \times \sqrt[3]{2} \\ = 3 \times 5 \times \sqrt[3]{2} \\ = 15 \sqrt[3]{2}$

4 0

3 years ago

Elena has 2 fewer hats then fran. Together, they have 14 hats. Which equation represents this situation.

Free_Kalibri [48]

<h2>Greetings!</h2>

Answer:

2x - 2 = 14

Step-by-step explanation:

Let x be the amount of hats Fran has, if Elena has -2 hats, then this can be shown by x - 2

So then

x + x - 2 = 14

2x - 2 = 14

You haven't asked this but to find the amount of hats they have, move the -2 over to the other side making it a +2:

2x = 14 + 2

2x = 16

x = 8

So Fran has 8 hats and Elena has 6 hats.

<h2>Hope this helps!</h2>

8 0

3 years ago

I need help with this plz

Ksju [112]

Answer:

The correct answer is D. 10.

Step-by-step explanation:

If Brandy earns 2 stars for every goal, and she scored 8 goals, then we need to multiply 8 by 2.

8 x 2 = 16

She looses 1/2 a star for every miss, and she missed the goal 12 times. Therefore, we need to multiply 1/2 by 12.

12 x 1/2 = 6

Therefore, Brandy lost 6 stars.

Now, we need to subtract the amount of stars Brandy earned by the amount that she lost.

16 - 6 = 10

Therefore, the correct answer is D. 10.

Hope this helps! :D

5 0

3 years ago

There are 10 acts on a talent show. An acrobat comedian dancer guitarist juggler magician pianist singer violinist and a whistle

hjlf

Answer:

The value of P (A) is 0.00833.

The value of P (B) is 0.00139.

Step-by-step explanation:

It is provided that there are 10 acts on a talent show.

The two events are defined as follows:

A: First three acts dancer, singer and the guitarist in any order

B: The comedian first guitarist second and pianist third

(1)

Compute the number of ways to select 3 acts from the 10 as follows:

${10\choose 3}=\frac{10!}{3!\cdot (10-3)!}=\frac{10!}{3!\cdot 7!}=120$

There are 120 ways to select 3 acts from the 10 and only 1 way to select a dancer, singer and the guitarist in any order.

Compute the probability of selecting a dancer, singer and the guitarist in any order as follows:

$P(A)=\frac{1}{120}=0.00833$

Thus, the value of P (A) is 0.00833.

(2)

Compute the number of ways to select 3 acts from the 10 (without replacement) and with order as follows:

$^{10}P_{3}=\frac{10!}{ (10-3)!}=\frac{10!}{ 7!}=720$

There are 720 ways to select 3 acts from the 10 with order and only 1 way to select the comedian first guitarist second and pianist third.

Compute the probability of selecting the comedian first guitarist second and pianist third as follows:

$P(B)=\frac{1}{720}=0.00139$

Thus, the value of P (B) is 0.00139.

6 0

3 years ago

The midpoint of line AB is (14,26). One endpoint of line AB is A(32, 40). What are the coordinates of B?

bogdanovich [222]

The coordinates of the midpoint:
$(\frac{x_1+x_2}{2}, \frac{y_1+y_2}{2})$
(x₁,y₁) - the coordinates of one endpoint
(x₂,y₂) - the coordinates of the other endpoint

The midpoint is (14,26).
One endpoint is A(32,40).
The other endpoint is B.

The x-coordinate of B:
$\frac{32+x}{2}=14 \ \ \ |\times 2 \\
32+x=28 \ \ \ |-32 \\
x=-4$

The y-coordinate of B:
$\frac{40+y}{2}=26 \ \ \ |\times 2 \\
40+y=52 \ \ \ |-40 \\
y=12$

The coordinates of B are (-4,12) - the answer is C.

4 0

3 years ago