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2 years ago

14

You are painting all four walls of a shed. Each wall is a rectangle with a length of 14 feet and a height of 8 feet. A gallon of

paint covers about 350 square feet. How many gallons of paint do you need in order to cover the walls?

1 answer:

Setler [38]2 years ago

7 0

It's 448 square feet so you'll require 1 and some. buy 2 gallons

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What does 5 degree & 8 degree equal

pickupchik [31]

Answer:

3 Degrees

Step-by-step explanation:

4 0

2 years ago

PetSmart.com sold the following varieties of dog food in June 2003.

aivan3 [116]

Let x be the number of bags of Nature's Recipe Venison Meal & Rice Canine 20 percent protein, y be the number of bags of Nutro Max Natural Dog Food 27 percent protein and z be the number of bags of PetSmart Premier Oven Baked Lamb 25 percent protein a dog breeder buys. He wants to make 300 pounds of a mix. Then

20x+17.5y+30z=300.

Now

in 20x pounds of Nature's Recipe Venison Meal & Rice Canine 20 percent protein is 0.2·20x=4x pounds of protein;
in 17.5y pounds of Nutro Max Natural Dog Food 27 percent protein is 0.27·17.5y=4.725y pounds of protein;
in 30z pounds of PetSmart Premier Oven Baked Lamb 25 percent protein is 0.25·30z=7.5z pounds of protein;
in 300 pounds of mix containing 22 percent protein is 0.22·300=66 pounds of protein.

Then 4x+4.725y+7.5z=66.

You get a system

$\left\{\begin{array}{l}20x+17.5y+30z=300\\4x+4.725y+7.5z=66.\end{array}\right.$

From the first equation $z=10-\dfrac{2}{3}x-\dfrac{7}{12}y.$ Substitute it into the second equation:

$4x+4.725y+7.5(10-\dfrac{2}{3}x-\dfrac{7}{12}y)=66.$

Simplify it:

$-x+\dfrac{7}{20}y=-9,\\ \\ 20x-7y=180.$

y must be divided by 20, then

y=0, x=9, z=10-6=4;
y=20, x=16, z is not a whole number;
y=40, x=23, z is not a whole number;
y=60, x=30, z=10-20-35<0;
thus, all other possible z will be <0.

Answer: 9 bags with 1st mix, 0 bags with 2nd mix and 4 bags with 3rd mix.

5 0

2 years ago

A marine biologist monitors the population of sunfish in a small lake. He records 800 sunfish in his first year, 600 sunfish in

Colt1911 [192]

Answer:

Let's use the variable y to represent the number of years passed since the first year.

The population on the first year (y = 0) was 800

The population in the second year (y = 1) was 600.

The ratio in which the population decreased can be calculated as:

R = 600/800 = 0.75

This means that 600 is the 75% of 800, this also means that between the first year and the second year, the population decreased by the 25%

Now let's look at the ratio between the second and third year (y = 2), the population the third year was 450

Now the ratio is:

R = 450/600 = 0.75

Same as before, then we already can see that the population will decrease by 25% each year.

The generic exponential decay equation is:

f(y) = A*(1 - r)^y

where:

A = initial population, in this case, is 800

y = our variable, in this case, represents the number of years

r = the amount that decreases per each unit of our variable, this must be written in decimal form. In this case, we know that the population decreases by 25% each year, and 25% written in decimal form is 0.25

Also, (1 - r) = R, where R is the ratio we found earlier.

To do this, we just divide 25% by 100% to get (25%/100% = 0.25)

Then our equation will be:

f(y) = 800*(1 - 0.25)^y

f(y) = 800*( 0.75)^y

1) We want to predict when the population will be 200.

to do this, we set:

f(y) = 200 = 800*( 0.75)^y

and solve it for y.

(200/800) = 0.75^y

(1/4) = 0.75^y

Now we can use the relationship:

Ln(a^x) = x*ln(a)

Then let's apply Ln( ) in both sides to get

ln(1/4) = y*ln(0.75)

ln(1/4)/ln(0.75) = y = 4.8 years.

This means that 4.8 years after the first year, the population will be around 200.

2) The population in the 25 th year (this is 24 years after the first one, so we take y = 24) is:

f(24) = 800*(0.75)^(24) = 0.80

Around this point, we will have no more sunfish in the lake.

7 0

2 years ago

Your teacher writes the fact below on the board.Using only mental math, will the answer be less than or greater than 5? How do y

Levart [38]

Answer:

Less than 5

Step-by-step explanation:

The eason behind the answer being less than 5 is because if you multiply something by a fraction that is less than a whole number, then you will get less than the original number you multiplied the fraction with.

Hope this helps :)

4 0

1 year ago

51.8 + (-0.8) i dont like how you suposse to have20 letters

Marizza181 [45]

Answer:

51

Step-by-step explanation:

51.8-0.8=51

8 0

2 years ago

Read 2 more answers