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3 years ago

Do you know number 11 to 13

Mathematics

1 answer:

umka21 [38]3 years ago

3 0

Answer:

see explanation

Step-by-step explanation:

(11)

Note the differences in the values of the sequence

5 - 2 = 3

8 - 5 = 3

11 - 8 = 3

Since the differences are common then these are the terms of an arithmetic sequence with explicit formula

$a_{n}$ = a₁ + (n - 1)d

where a₁ is the first term and d the common difference, thus

$a_{n}$ = 2 + 3(n - 1) = 2 + 3n - 3 = 3n - 1 ← explicit formula

(12)

A recursive formula allows the next term in the sequence to be found from the previous term.

To obtain the next term add 3 to the previous term, thus

$a_{n+1}$ = $a_{n}$ + 3 , with a₁ = 2

(13)

Using the explicit formula, then

$a_{20}$ = (3 × 20) - 1 = 60 - 1 = 59

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Fifteen dozen eggs were needed for baking four wedding cakes. The first cake

Mazyrski [523]

Answer:

96 eggs

Step-by-step explanation:

A dozen is equal to 12 eggs, so 15 dozen is equal to 180 eggs

(Because 15*12 = 180)

We already know how many eggs are required for the 1st cake: 12 eggs.

Then it says "each successive cake needs twice as many eggs as the previos cake".

(Successive means the cake directly after the previous cake)

Here's how we find the number of eggs needed for the 2nd cake:

The 1st cake needed 12 eggs, and because the 2nd cake is directly after the 1st cake, we are going to need two times the amount of 12 eggs.

This equation represents the above scenario:

12*2 = 24

So we need 24 eggs for the 2nd cake.

Now we repeat this process for the 3rd cake, finding twice the amount of eggs from the 2nd cake to find the amount of eggs needed for the 3rd cake:

24*2 = 48

And we repeat it once more for the 4th cake, using the eggs from the 3rd cake:

48*2 = 96

So here's the list of how many eggs are required for each of the cakes:

1st cake: 12

2nd cake: 24

3rd cake: 48

4th cake: 96

If you add all the eggs from each of the cakes, you will get 180, which is the number of eggs needed for all four cakes. So our answer is correct.

Hope this helps (●'◡'●)

7 0

4 years ago

A volleyball curt is 61 feet lenght and 21 feet wide. How much rope will you use to mark the outline on the court?

lozanna [386]

So finding the rope is kind of like finding the perimeter. Add 61+61+21+21 and you will get 164 feet.

8 0

3 years ago

_% of 1.50 = 0.30? Im confused

ELEN [110]

0.30/1.50= 0.2= 20%
20% of 1.50 = 0.30

5 0

3 years ago

Read 2 more answers

Stephanie has an aquarium that is in the shape of a right rectangular prism, 50 centimetres long, 25 centimetres wide and 30 cen

Bess [88]

To solve this, we are going to use the volume formula for a rectangular prism: $V=lwh$
where
$V$ is the volume of the prism
$l$ is the length of the prism
$w$ is the width of the prism
$h$ is the height of the prism

We are also using the volume of a sphere formula: $V= \frac{4}{3} \pi r^{3}$
where
$V$ is the volume of the sphere
$r$ is the radius of the sphere

Part A: Since she wants a layer of marbles in the bottom of the tank about 5 centimeters deep, the height of this little rectangular prism will be 5 centimeters, so $h=5$ . Since the other measures of our little rectangular prism are the same as the aquarium, $l=50$ and $w=25$ . Lets replace those values in our volume formula:
$V=lwh$
$V=(50)(25)(5)$
$V=6250 cm^{3}$
Now that we know that she wants to cover a volume of 6250 $cm^{3}$ with marbles, lets find the volume of each marble.
We know that the diameter of each marble is 1 cm. Since the radius is of a sphere is half its diameter, $r= \frac{1}{2} =0.5$ . Lets replace that value in our volume formula:
$V= \frac{4}{3} \pi r^{3}$
$V= \frac{4}{3} \pi (0.5)^{3}$
$V=0.52 cm^{3}$
Now, let $x$ the number of marbles she will need to cover a volume of 6250 $cm^{3}$ :
$0.52x=6250$
$x= \frac{6250}{0.52}$
$x=12019.23$
Since we know that each bag of marbles has 500 marbles, we are going to divide the number of marbles she will need by the number of marbles in each bag:
$\frac{12019.23}{500} =24.03$

We can conclude that to fill a layer of 5 cm with marbles, she will need 24 bags of marbles.

Part B: We know that she already have 5 cm of her aquarium filled with marbles, and that she also added water until it’s level is 3 centimeters below the top of the tank, so to find the height of this new rectangular prism, we are going to subtract 5 cm plus 3 cm from the original height of her aquarium:
 $h=30-(5+8)$
$h=30-13$
$h=17cm$
Since the other measures of our little rectangular prism are the same as the aquarium, $l=50$ and $w=25$ . Lets replace those values in our volume formula:
$V=lwh$
$V=(50)(25)(17)$
$V=21250cm^{3}$
Remember that $1litre=1000cm^{3}$ . So:
$(21250cm^3)( \frac{1litre}{1000cm^{3})} =21.25liters$

We can conclude that there are 21.25 liters of water in the tank.

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3 years ago

100 points don't tell me wrong what is 1+1-1+1-1+1-1x2839

algol13

Answer:

Step-by-step explanation:

1+1-1+1-1+1-1×2839

1×2839

=2839

4 0

3 years ago

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