Two step equation -5=d/4+3

David wants to hang a mirror in his room. The mirror and frame must have an area of 8 square feet. The mirror is 2 feet wide and

andreyandreev [35.5K]

Represent the thickness of the frame by x. Framing the mirror will increase both its length and width by 2x. The area of the mirror with the frame is the product of the length and width which can mathematically be expressed as,

A = (3 + 2x)(2 +2x) = 8

The equation above can be simplified into 4x^2 + 10x -2 = 0. This equation can still be further simplified by dividing it by 2. However, it will give an answer which is not found on the choices. Thus, the answer is the third choice.

5 0

2 years ago

$53,000 is placed in an investment account that grows at a fixed rate of 2% (compound growth) per year. how much is in the accou

ella [17]

Answer:

$57,369

Step-by-step explanation:

We have been given that an amount of $53,000 is placed in an investment account that grows at a fixed rate of 2% (compound growth) per year. We are asked to find the amount in the account after 4 years.

To solve our given problem we will use compound interest formula.\

$A=P(1+\frac{r}{n})^{nt}$ , where,

A = Final amount after t years,

P = Principal amount,

r = Annual interest rate in decimal form,

n = Number of times interest is compounded per year,

t = Time in years.

Let us convert our given rate in decimal form.

$2\%=\frac{2}{100}=0.02$

Upon substituting our given values in compound interest formula we will get,

$A=\$53,000(1+\frac{0.02}{1})^{1*4}$

$A=\$53,000(1+0.02)^{4}$

$A=\$53,000(1.02)^{4}$

$A=\$53,000*1.08243216$

$A=\$57368.90448\approx \$57,369$

Therefore, an amount of $57,369 will be in the account after 4 years.

3 0

2 years ago

Wayne Gretsky scored a Poisson mean six number of points per game. sixty percent of these were goals and forty percent were assi

BartSMP [9]

Answer:

a) The mean for the total revenue he earns per game is of 13.2K while the standard deviation is of 3.63K.

b) 0.05 = 5% probability that he has four goals and two assists in one game

Step-by-step explanation:

In hockey, a point is counted for each goal or assist of the player.

In a Poisson distribution, the probability that X represents the number of successes of a random variable is given by the following formula:

$P(X = x) = \frac{e^{-\mu}*\mu^{x}}{(x)!}$

In which

x is the number of sucesses

e = 2.71828 is the Euler number

$\mu$ is the mean in the given interval. The standard deviation is the square root of the mean.

(a) Find the mean and standard deviation for the total revenue he earns per game.

60% of six are goals, which means that 60% of the time he earned 3K.

40% of six are goals, which means that 40% of the time he earned 1K.

The mean is:

$\mu = 6*0.6*3 + 6*0.4*1 = 13.2$

The standard deviation is:

$\sigma = \sqrt{\mu} = \sqrt{13.2} = 3.63$

The mean for the total revenue he earns per game is of 13.2K while the standard deviation is of 3.63K.

(b) What is the probability that he has four goals and two assists in one game

Goals and assists are independent of each other, which means that we find the probability P(A) of scoring four goals, the probability P(B) of getting two assists, and multiply them.

Probability of four goals:

60% of 6 are goals, which means that:

$\mu = 6*0.6 = 3.6$