please answer, click on file, thank you ​

Answer:

A- 480

Step-by-step explanation:

First, I'm going to work out 25% of 1200 for the before 1980 pennies.

10% = 120

20% = 240

5% = 60

240 + 60 = 300 pennies before 1980.

Next, work out 35% of 1200 instead.

20% = 240

+ 10%

30% = 360

+ 5% = 60

35% = 420 pennies from 1980-2000

Finally, work out how many pennies are leftover.

300 + 420 = 720

1200 - 720 = 480

A is the answer.

Hope this helps and have a good day!

Answer:

17.08

Step-by-step explanation:

When it reaches its maximum, suppose that y = 0

Therefore you will need to factorise and solve

-16x^2 + 267 x + 107 = 0

Here you can use the quadratic equation[tex]\frac{-b+-\sqrt{b^{2}-4ac } }{2a}[/tex]

Where you will get x = -0.39 seconds or 17.08 seconds (rounded to 2 decimal places according to the question

Because -0.39 is negative, this answer can be deleted

Leacing x = 17.08 seconds

Using the permutation and the combination formula, we have that:

a) The first three finishers can be awarded medals in 504 ways.

b) They can be arranged in 252 ways.

c) In how many ways can 4 students form a team from a set of 8.

Combination formula:

[tex]C_{n,x}[/tex] is the number of different combinations of x objects from a set of n elements, given by:

[tex]C_{n,x} = \frac{n!}{x!(n-x)!}[/tex]

Permutation formula:

The number of possible permutations of x elements from a set of n elements is given by:

[tex]P_{(n,x)} = \frac{n!}{(n-x)!}[/tex]

Item a:

Order is important, as the finishers are ranked, hence:

[tex]P_{(9,3)} = \frac{9!}{6!} = 504[/tex]

The first three finishers can be awarded medals in 504 ways.

Item b:

The order is not important, hence:

[tex]C_{10,5} = \frac{10!}{5!5!} = 252[/tex]

They can be arranged in 252 ways.

Item c:

Situation in which the order is not important, hence, for example, in how many ways can 4 students form a team from a set of 8.

For more on permutation/combination, you can take a look at https://brainly.com/question/25247153

Answer:

4

Step-by-step explanation:

Answer:

  2 bottles

Step-by-step explanation:

The 15 trees will need ...

  (15 trees)×(10.5 fl oz/tree) = 157.5 fl oz

This is about ...

  (157.5 fl oz)/(33.814 fl oz/L) ≈ 4.66 L

This is just slightly more than the quantity available in 1 bottle. It amounts to ...

  4.66 L/(4.1 L/bottle) ≈ 1.14 bottles

We assume that only whole bottles can be purchased, and that we do not have an inventory of fertilizer on hand.

2 bottles are needed to fertilize 15 trees

Answer:

2/5 × 3/2

Step-by-step explanation:

Answer: 62

Step-by-step explanation:

100 - x = 38

x =62

Answer:

37.5

Step-by-step explanation:

multiply 50 by .75

same as

50/4=12.5+25=37.5

D = (7, -9)

E = (8, -10)

hope this helps!

Answer:

  9 plates

Step-by-step explanation:

The number of plates Kyle can make is the GCF of 9 and 18. Since 9 is a factor of 18, that GCF is 9.

Kyle can make 9 plates, each containing 1 avocado roll and 2 cucumber rolls.

Answer:1/16 squared

Step-by-step explanation:

1/4*1/4

4*4=16

1/16

Answer:

75%

Step-by-step explanation:

Here are step-by-step instructions showing you how we calculated 39 out of 52 as a percentage:

The first step is to divide 39 by 52 to get the answer in decimal form:

39 / 52 = 0.7500

Then, we multiplied the answer from the first step by one hundred to get the answer as a percentage:

0.7500 * 100 = 75.00%

Answer:

y=2/3-5x/6

Step-by-step explanation:

Answer:

x>-4

Step-by-step explanation:

Hope this helps! Pls give brainliest! Also sub to kgir633 on yt.

Answer:

Warrior WiFi is better because it costs 167.50 for 175 texts.

Step-by-step explanation:

2x175 = 350 + 20 = 370

0.50x175 = 87.5 + 80 = 167.5

Answer:

Step-by-step explanation:

y = kx ;

k = [tex]\frac{y}{x}[/tex] ; x = [tex]\frac{y}{k}[/tex]

~~~~~~~~~~~~~

k = [tex]\frac{1}{2}[/tex] ÷ 1 = [tex]\frac{1}{2}[/tex]

[tex]y_{1}[/tex] = [tex]\frac{1}{2}[/tex] × ( - 8 ) = - 4

[tex]y_{2}[/tex] = [tex]\frac{1}{2}[/tex] × ( - 4 ) = - 2

[tex]y_{3}[/tex] = [tex]\frac{1}{2}[/tex] × 2 = 1

[tex]x_{5}[/tex] = [tex]\frac{1}{3}[/tex] ÷ [tex]\frac{1}{2}[/tex] = [tex]\frac{2}{3}[/tex]

[tex]x_{6}[/tex] = - [tex]\frac{1}{4}[/tex] ÷ [tex]\frac{1}{2}[/tex] = - [tex]\frac{1}{2}[/tex]

[tex]x_{7}[/tex] = 0

( x , y ) : ( - 8 , - 4 ), ( - 4 , - 2 ), ( 2 , 1 ), ( 1 , [tex]\frac{1}{2}[/tex] ), ( [tex]\frac{2}{3}[/tex] , [tex]\frac{1}{3}[/tex] ), ( - [tex]\frac{1}{2}[/tex] , - [tex]\frac{1}{4}[/tex] ), ( 0 , 0 )

Answer:

2/63

Step-by-step explanation:

I'm going to assume that the x is a multiplication symbol.

7 x 9 = 63

Therefore, the simplest form would be 2/63

Answer:x=-1, y=2

Step-by-step explanation:

Summing these equations, we will obtain,

-7x =7

Therefore, x=-1

If we put x in the first equation,

(-3*-1)-5y=-7

3-5y=-7

-5y=-10

y=2

Answer:

x=-1, y=1

Step-by-step explanation:

-3x-5y=-7

-4x+5y=14

-7x=7

x=-1

-3x-5y=-7

-3(-1)-5y=-7

3-5y=-7

-5y=-10

y=2

Answer:

$142.92

Step-by-step explanation:

120 * 1.06^3 = 142.92192

Answer:

= 5l. 66 in^3

Step-by-step explanation:

Area of cross section (A) = 1/2×b×h

=1/2 ×3.5×4.1

=7.175

Volume =AXH

= 7.175× 7.2

= 5l. 66 in^3

Answer:

P(x)= x^3 - 4x^2 + 16x - 64

Step-by-step explanation:

First, let’s find all of the zeroes. If the question is asking for a degree 3 polynomial, than there has to be more than 2 zeroes. The complex conjugates theorem states that if a+bi is a zero, than a-bi has to be a zero as well. So if 4i is a zero, than -4i has to be a zero as well. By looking at the zeroes, you can write them as a linear factorization.

(x-4)(x+4i)(x-4i)

If you foil all of it, you will get x^3 - 4x^2 + 16x - 64.

Answer:

i think x = -7, y = -6

Step-by-step explanation:

good luck

Answer:

The correct answers are:

A) 60 miles; and B) 3.375 hours.

Explanation:

We will use the equation d = rt for this.

For the first leg of the trip, the bird travels 20 miles per hour for x hours.  This gives us the equation

d = 20x

For the return trip, the bird travels 4 miles per hour slower, so 20-4 = 16 miles per hour.  He also travels 6 miles less than the return distance, for x hours:

d-6 = 16x

To isolate d, we will add 6 to each side:

d-6+6 = 16x+6

d = 16x+6

We will set the two equations equal to one another, since they both equal d:

20x = 16x+6

Subtract 16x from each side:

20x-16x = 16x+6-16x

4x = 6

Divide both sides by 4:

4x/4 = 6/4

x = 1.5

He travels for 1.5 hours both times.

The first time, 1.5 hours at 20 miles per hour is:

d = 1.5(20) = 30 miles

The original trip is 30 miles.  This makes the entire trip 30(2) = 60 miles.

On the return trip, he travels 30-6 = 24 miles at 16 miles per hour:

24 = 16x

Divide both sides by 16:

24/16 = 16x/16

1.5 = x

If he goes 24 miles in 1.5 hours at 16 miles per hour, we can use a proportion to find the time it takes for the entire return trip:

24/1.5 = 30/x

Cross multiplying,

24*x = 1.5(30)

24x = 45

24x/24 = 45/24

x = 1.875

This gives him a total time of 1.5+1.875 = 3.375 hours

Step-by-step explanation:

Answer:

c

Step-by-step explanation:

_6x -9y =15

_6x÷3=-2x

9y÷3=3y

15÷3=5

so,_2x -3y =5

Answer:

2a + 7

Step-by-step explanation:

2a + 6 + 1 ← collect like terms

= 2a + (6 + 1)

= 2a + 7

Answer:

c

Step-by-step explanation:

The correct answer is option D.

A system of inequalities is a set of two or more inequalities in one or more variables. Systems of inequalities are used when a problem requires a range of solutions, and there is more than one constraint on those solutions.

Learn more about the system of inequalities here: brainly.com/question/4870108

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