Pre algebra help ( will give brainliest ) sorry if it's hard to see

You decide to put $100 in a saving account to save for a $3000 down payment on a new car. if the account has an interest rate of

valkas [14]

Hi there
The formula is
A=p (1+r/k)^kt
A future value 3000
P present value 100
R interest rate 0.02
K compounded monthly 12
T time?
We need to solve for t
T=[log (A/p)÷log (1+r/k)]÷k
T=(log(3,000÷100)÷log(1+0.02÷12))÷12
T=170.202 years

So it's a
Hope it helps

4 0

3 years ago

The mean height of women in a country (ages 20-29) is 64 4 inches A random sample of 50 women in this age group is selected What

Simora [160]

Answer:

0.0721 = 7.21% probability that the mean height for the sample is greater than 65 inches.

Step-by-step explanation:

To solve this question, we need to understand the normal probability distribution and the central limit theorem.

Normal Probability Distribution:

Problems of normal distributions can be solved using the z-score formula.

In a set with mean $\mu$ and standard deviation $\sigma$ , the z-score of a measure X is given by:

$Z = \frac{X - \mu}{\sigma}$

The Z-score measures how many standard deviations the measure is from the mean. After finding the Z-score, we look at the z-score table and find the p-value associated with this z-score. This p-value is the probability that the value of the measure is smaller than X, that is, the percentile of X. Subtracting 1 by the p-value, we get the probability that the value of the measure is greater than X.

Central Limit Theorem

The Central Limit Theorem establishes that, for a normally distributed random variable X, with mean $\mu$ and standard deviation $\sigma$ , the sampling distribution of the sample means with size n can be approximated to a normal distribution with mean $\mu$ and standard deviation $s = \frac{\sigma}{\sqrt{n}}$ .

For a skewed variable, the Central Limit Theorem can also be applied, as long as n is at least 30.

Mean of 64.4 inches, standard deviation of 2.91

This means that $\mu = 64.4, \sigma = 2.91$

Sample of 50 women

This means that $n = 50, s = \frac{2.91}{\sqrt{50}}$

What is the probability that the mean height for the sample is greater than 65 inches?

This is 1 subtracted by the p-value of Z when X = 65. So

$Z = \frac{X - \mu}{\sigma}$

By the Central Limit Theorem

$Z = \frac{X - \mu}{s}$

$Z = \frac{65 - 64.4}{\frac{2.91}{\sqrt{50}}}$

$Z = 1.46$

$Z = 1.46$ has a p-value of 0.9279

1 - 0.9279 = 0.0721

0.0721 = 7.21% probability that the mean height for the sample is greater than 65 inches.

8 0

3 years ago

Which expression is equivalent to 5y^3/(5y)^-2

Serggg [28]

Answer:

5^3 y^5

125 y^5

Step-by-step explanation:

5y^3/(5y)^-2

Distribute the exponent in the denominator

5y^3/(5 ^-2 y^-2)

A negative exponent in the denominator brings it to the numerator

5y^3 5 ^2 y^2

Combine like terms

5 * 5^2 * y^3 5^2

We know that a^b * a^c = a^(b+c)

5^(1+2) * y^( 3+2)

5^3 y^5

125 y^5

6 0

3 years ago

How do you graph: y≤−4x+40 and y≤10

Arturiano [62]

Answer:

See attached picture.

Step-by-step explanation:

To graph linear inequalities, use the y=mx + b form to graph using the slope and y-intercept.

y ≤ -4x + 40 has slope -4 and y-intercept (0,40).

Start at (0,40) and mark it. Then move down 4 units and to the right 1. Mark this point at (1,36). Connect the points with a solid line since the inequality has equal to. Substitute a point like (0,0) to test where the solution set is.

0 ≤ -4(0) + 40

0 ≤ 0 + 40

0 ≤ 40

This is true so shade to the left of the line.

To graph y ≤ 10 mark a point on the y-axis at (0,10). Draw a horizontal solid line through the point. Then shade below the line.

7 0

3 years ago

Please help I will mark brainlist if correct

MakcuM [25]

The admission fee at a fair is $2.00 for children and $4.00 for adults.

On Saturday 2,500 people entered the fair and $7,000.00 were collected.

How many children and how many adults attended? Give your answer, using x for children, y for adults.

Form of: x =, and y =

Let K = no. of children

Let A = no. of adults

2500 people mean

Kids + Adults

K + A = 2500

K = 2500 – A

2K + 4A = 7000

K + 2A = 3500

(2500 – A) + 2A = 3500

A = 3500 – 2500

(A = 1000, adults)

K = 2500 – A

K = 2500 -1000

(K = 1500, Kids)

CHECK:

1500*2 = $3000

1000*4 = $4000

(Total = $7000, people.).

Hope this helps:

6 0

3 years ago