Find the area under the standard normal curve between z=0.45 and z=1.13

HELP ASAP PLEASE!!!!!

zysi [14]

35) 48 cents each!
36) 297 miles a day!

8 0

4 years ago

Read 2 more answers

Find the solution to the system of equations,x+3y and 2x+4y=8

Sati [7]

Answer:

x = -7/3y + 8/3

y = -3/7x + 8/7

Step-by-step explanation:

First, set the equations next to each other to find x and y, I'll start with x:

x + 3y + 2x + 4y = 8

Combine like terms

3x + 7y = 8

Subtract both sides by 7y

3x + 7y - 7y = 8 - 7y

3x = 8 - 7y

I'll re-order the equation to make it easier to divide

3x = -7y + 8

Divide both sides by 3

3x / 3 = -7y + 8 /3

x = -7/3y + 8/3

If you need decimals just divide with a calculator

Now to find y:

We already combined like terms so we don't need to do that again...

3x + 7y = 8

Subtract both sides by 3x

3x - 3x + 7y = 8 - 3x

7y = 8 - 3x

I'll reorder the equation once again so the variable comes first

7y = -3x + 8

Divide both sides by 7

7y / 7 = -3x + 8 / 7

y = -3/7x + 8/7

Again, use a calculator to divide completely for decimals.

6 0

3 years ago

$1000 is invested at the beginning of each year for 10 years. The rate of interest is fixed at 7.5% per annum. Interest is compo

Lemur [1.5K]

Presumably you are saying that the 7.5% is the actual real effective per annum rate since you did not include a compounding interval. Therefore if you let R = 1.075 which is 7.5%, X = $1,000 and F(n) be the balance after n years then you can figure it out by thinking about what happens. After one year, your balance is:

F(1) = X * R

After two years, your balance is:

F(2) = ( F(1) +X ) * R
.:
F(2) = X * R^2 + X * R

After three years, your balance is:

F(3) = ( F(2) + X ) * R
F(3) = X * R^3 + X * R^2 + X * R

You can see that the general form is:

F(n) = X * summation of R^k for k = 1 to n

Applying the summation of a geometric sequence equation and you get:

F(n) = X * ( ( 1 - R^(n+1) ) / ( 1 - R ) - 1 )

Therefore the total value of the investments after 10 years is:

F(10) = $1,000 * ( ( 1 - 1.075^11 ) / ( 1 - 1.075 ) - 1 )
F(10) = $15,208.12

If you blindly use the programs in the business calculators, you'll get the wrong answer of $14,147.09 because those calculators assume that the deposit is made at the end of the year not at the beginning. The equation is slightly easier to work out that way as the summation of the geometric sequence would be for k from 0 to n-1. That's one of the downfalls of relying on those calculators, you don't actually understand what's happening.

Now the portion of that which is from the first $1,000 payment is $1,000 * 1.075^10 which is $2,061.03

5 0

3 years ago

Sarah used a scale of ½ inch = 3 feet for a drawing of her business. On the drawing, a rectangular room measures 2 ½ inches by 3

Korolek [52]

Answer:

The new carpet will cost $1279.13 to the nearest cent

Step-by-step explanation:

The given is:

1. Sarah used a scale of $\frac{1}{2}$ inch = 3 feet

2. On the drawing, a rectangular room measures $2\frac{1}{2}$ inches

by $3\frac{3}{4}$ inches

3. Sarah wants to purchase new carpet for the room that costs $3.79

per square foot

We need to find much the new carpet will cost

∵ The scale is 0.5 inch = 3 feet

∵ The dimensions of the room on the drawing are $2\frac{1}{2}$ inches and

$3\frac{3}{4}$ inches

∵ $2\frac{1}{2}$ = 2.5

∵ $3\frac{3}{4}$ = 3.75

Use the ratio method

→ inches : feet

→ 0.5 : 3

→ 2.5 : x

→ 3.75 : y

- By using cross multiplication

∴ 0.5 x = 2.5 × 3

∴ 0.5 x = 7.5

- Divide both sides by 0.5

∴ x = 15 feet

∴ 0.5 y = 3.75 × 3

∴ 0.5 y = 11.25

- Divide both sides by 0.5

∴ y = 22.5 feet

∴ The actual dimensions of the room are 15 feet and 22.5 feet

Now lets find the area of the room which is the area of the carpet

∵ Area of the carpet = 15 × 22.5

∴ Area of the carpet = 337.5 feet²

∵ The cost of the carpet is $3.79 per square feet

∴ The cost of the carpet = 3.79 × 337.5 = 1278.125

∴ The cost of the carpet = $1279.13 to the nearest cent

The new carpet will cost $1279.13 to the nearest cent

Learn more:

You can learn more about ratio in brainly.com/question/13076219

#LearnwithBrainly

8 0

4 years ago

Solve for x.

Flauer [41]

I have to say its
−64 and 64

4 0

3 years ago

Read 2 more answers