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Nimfa-mama [501]

3 years ago

14

A purse contains five 10$, four 5$, and eight 1$ bills. If the bills are selectedone by one in random order, what is the probabi

lity that at least two bills mustbe selected to obtain a first 10$?

1 answer:

Free_Kalibri [48]3 years ago

3 0

Answer:

0.67

Step-by-step explanation:

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What is 34342424×453?

zloy xaker [14]

Answer:

1.555711807*10^10

Step-by-step explanation:

4 0

3 years ago

Read 2 more answers

Calculate the sample mean and sample variance for the following frequency distribution of heart rates for a sample of American a

spin [16.1K]

Answer:

$Mean = 68.9$

$s^2 =18.1$ --- Variance

Step-by-step explanation:

Given

$\begin{array}{cccccc}{Class} & {51-58} & {59-66} & {67-74} & {75-82} & {83-90} \ \\ {Frequency} & {6} & {3} & {11} & {13} & {4} \ \end{array}$

Solving (a): Calculate the mean.

The given data is a grouped data. So, first we calculate the class midpoint (x)

For 51 - 58.

$x = \frac{1}{2}(51+58) = \frac{1}{2}(109) = 54.5$

For 59 - 66

$x = \frac{1}{2}(59+66) = \frac{1}{2}(125) = 62.5$

For 67 - 74

$x = \frac{1}{2}(67+74) = \frac{1}{2}(141) = 70.5$

For 75 - 82

$x = \frac{1}{2}(75+82) = \frac{1}{2}(157) = 78.5$

For 83 - 90

$x = \frac{1}{2}(83+90) = \frac{1}{2}(173) = 86.5$

So, the table becomes:

$\begin{array}{cccccc}{x} & {54.5} & {62.5} & {70.5} & {78.5} & {86.5} \ \\ {Frequency} & {6} & {3} & {11} & {13} & {4} \ \end{array}$

The mean is then calculated as:

$Mean = \frac{\sum fx}{\sum f}$

$Mean = \frac{54.5*4+62.5*3+70.5*11+78.5*13+86.5*4}{6+3+11+13+4}$

$Mean = \frac{2547.5}{37}$

$Mean = 68.9$ -- approximated

Solving (b): The sample variance:

This is calculated as:

$s^2 =\frac{\sum (x - \overline x)^2}{\sum f - 1}$

So, we have:

$s^2 =\frac{(54.5-68.9)^2+(62.5-68.9)^2+(70.5-68.9)^2+(78.5-68.9)^2+(86.5-68.9)^2}{37 - 1}$

$s^2 =\frac{652.8}{36}$

$s^2 =18.1$ -- approximated

5 0

3 years ago

If f(x)=3x-2 and g(x)=2x+1,find (f+g)(x)

gizmo_the_mogwai [7]

Answer:

f(x) + g(x) = 3x - 2 + 2x + 1

(f + g)(x) = 5x - 1

5 0

2 years ago

A faucet in a large tank can fill the tank in 12 hours. However, there is a hose in the tank which would be able to empty the ta

Kruka [31]

It would take the faucet 18 hours to fill the tank because 18/12=1.5. That means it will be 1.5 times slower to fill the tank up with the hose on. 1.5*12=18.

7 0

3 years ago

A sequence is represented by the formula an=-5+a(n-1). If a4 = 20, what is the 6th term in the sequence?

Citrus2011 [14]

Answer:

<u>10</u>

Step-by-step explanation:

Formula :

aₙ = -5 + aₙ₋₁

Finding a₅ :

a₅ = -5 + a₄
a₅ = -5 + 20
a₅ = 15

Finding a₆ :

a₆ = -5 + a₅
a₆ = -5 + 15
a₆ = <u>10</u>

4 0

2 years ago