The thermostat for a house is set to 68 °F, but the actual temperature may vary

One number is seven less than five times another. If their sum is decreased by four the result is one. Find the numbers

juin [17]

Let the number be Y .
Y is seven
less than 5 times another (let that other be X)
Y=7-5X
sum of both Y and X minus 4 gives one
Y+X-4=1
now solve both equations .

6 0

3 years ago

32% of college students say they use credit cards because of the rewards program. You randomly select 10 college students and a

Tems11 [23]

Answer:

a) $P(X=2)=(10C2)(0.32)^2 (1-0.32)^{10-2}=0.211$

b) $P(X> 2)=1-P(X\leq 2)=1-[0.0211+0.0995+0.211]=0.668$

c) $P(2 \leq x \leq 5)=0.211+0.264+0.218+0.123=0.816$

Step-by-step explanation:

1) Previous concepts

The binomial distribution is a "DISCRETE probability distribution that summarizes the probability that a value will take one of two independent values under a given set of parameters. The assumptions for the binomial distribution are that there is only one outcome for each trial, each trial has the same probability of success, and each trial is mutually exclusive, or independent of each other".

2) Solution to the problem

Let X the random variable of interest, on this case we now that:

$X \sim Binom(n=10, p=0.32)$

The probability mass function for the Binomial distribution is given as:

$P(X)=(nCx)(p)^x (1-p)^{n-x}$

Where (nCx) means combinatory and it's given by this formula:

$nCx=\frac{n!}{(n-x)! x!}$

Part a

$P(X=2)=(10C2)(0.32)^2 (1-0.32)^{10-2}=0.211$

Part b

$P(X> 2)=1-P(X\leq 2)=1-[P(X=0)+P(X=1)+P(X=2)]$

$P(X=0)=(10C0)(0.32)^0 (1-0.32)^{10-0}=0.0211$

$P(X=1)=(10C1)(0.32)^1 (1-0.32)^{10-1}=0.0995$

$P(X=2)=(10C2)(0.32)^2 (1-0.32)^{10-2}=0.211$

$P(X> 2)=1-P(X\leq 2)=1-[0.0211+0.0995+0.211]=0.668$

Part c

$P(2 \leq x \leq 5)=P(X=2)+P(X=3)+P(X=4)+P(X=5)$

$P(X=2)=(10C2)(0.32)^2 (1-0.32)^{10-2}=0.211$

$P(X=3)=(10C3)(0.32)^3 (1-0.32)^{10-3}=0.264$

$P(X=4)=(10C4)(0.32)^4 (1-0.32)^{10-4}=0.218$

$P(X=5)=(10C5)(0.32)^5 (1-0.32)^{10-5}=0.123$

$P(2 \leq x \leq 5)=0.211+0.264+0.218+0.123=0.816$

6 0

3 years ago

An electrician has a piece of wire that is 4 and 3/8 centimeters long. She divides the wire into pieces that are 1 and 2/3 centi

Vlada [557]

Answer:

She has approximately 3 pieces ( 2.625)

Step-by-step explanation:

To get the number of pieces, we need to divide the length of the wire by the individual length of the pieces.

To get the division done, it would be easier to convert what we have into improper fractions

For the piece of wire, the length which is 4 and 3/8 centimeters long will be 35/8 centimeters

while;

the individual length of each of the piece which is 1 and 2/3 centimeters long will be 5/3 centimeters

The number of pieces is thus 35/8 divided by 5/3 = 35/8 * 3/5 = 21/8 = 2.625 which is approximately 3 pieces

6 0

3 years ago

On a coordinate plane, point B(–6, 1) is translated to B prime(–3, –2). Indira uses these steps to find a rule to describe the t

Lunna [17]

Answer:

The rule of the translation is (x,y) -----> (x+3,y-3)

The translation is 3 units at right and 3 units down

Step-by-step explanation:

we have that

The translation of point B to point B' is

B(-6,1) -----> B'(-3,-2)

so

(x,y) -----> (x+a,y+b)

B(-6,1) ----> (-6+a,1+b)

Find the value of a

$-6+a=-3$

solve for a

$a=-3+6\\a=3$

Find the value of b

$1+b=-2$

solve for b

$b=-2-1\\b=-3$

therefore

The rule of the translation is

(x,y) -----> (x+3,y-3)

That means ----> The translation is 3 units at right and 3 units down

3 0

3 years ago

Read 2 more answers

Abeline is creating a box design for a company. The front, back, and sides will be painted, but the top and bottom will not be p

just olya [345]

Answer:

it is the first one

Step-by-step explanation:

4 0

3 years ago