A tin of paint covers a surface area of 50m2. Each tin costs £5.60. The entire surface of a solid cylindrical rod with diameter 8m and height 12m needs to be painted. Find the minimum cost of painting the rod. (NO NEED FOR EXLENATION)​

Answer:

see below

Step-by-step explanation:

b - 4 = 3

Add 4 to each side

b - 4+4 = 3+4

b = 7

-32 = 8w

Divide by 8

-32/8 = 8w/8

-4 = w

n/7 = -4

Multiply by 7 to each side

n/7 *7 = -4*7

n = -28

let the n'th term be called x, and the value of the term y,

then there is a function y=a*x + b

that will give us all term we want.

this formula is also used for straight lines.

we just need a and b. we already got two data points. we can just plug the known x/y pairs into the formula

10.5 = a*12 + b

13.5 = a*18 + b

now lets manipulate these lines.

multiply the first line by 3 and the second line by 2

31.5 = a*36 + 3b

27 = a*36 + 2b

subtract the second line from the first line

4.5 = b

yey, we now know b, let's plus b into either line from above, I'll go with the first one, looks easier.

10.5 = a*12 + 4.5

6 = a*12

0.5 = a

now y=a*x + b can be filled with a and b

y = 0.5 * x + 4.5

for x=1 (the first term) it's f(1)=5

each step is 0.5, hence the common difference.

(13.5-10.5)/(18-12)

= 3 / 6

= 0.5

we got the comment difference by looking at the full difference over 6 steps and divined by these 6 steps.

from step 12 to step one it's 11 steps down

10.5 - 0.5*11

= 10.5 - 5.5

= 5

The only 2-digit number that is lesser than 50 and the sum of its digits remain unaffected despite being multiplied by a number < 1 would be '18.'

To prove, we will look at some situations:

If we add up the two digits of 18. We get,

[tex]1 + 8 = 9[/tex]

And we multiply 18 by 2 which is greater than 1. We get,

[tex]18[/tex] × [tex]2 = 36[/tex]

The sum remains the same i.e. [tex]3 + 6 = 9[/tex]

Similarly,

If 18 is multiplied to 3(greater than 1), the sum of the two digits comprising the number still remains the same;

[tex]18[/tex] × [tex]3 = 54[/tex]

where (5 + 4 = 9)

Once more,

Even if 18 is multiplied to 4 or 5(greater than 1), the sum of its digits will still be 9.

 [tex]18[/tex] × [tex]4 = 72[/tex]

[tex](7 + 2 = 9)[/tex]

[tex]18[/tex] × [tex]5 = 90[/tex]

[tex](9 + 0 = 9)[/tex]

Thus, 18 is the answer.

Learn more about 'numbers' here: brainly.com/question/1624562

Answer:

Step-by-step explanation:

from the picture:

QP = QR

and

QR = RS

so

PQ + RS = QS

Answer:

x = 155º

Step-by-step explanation:

y = 25°    {Vertically opposite angles}

x + y = 180    {Co-interior angles are supplementary}

x + 25 = 180

Subtract 25 from both sides

x = 180 - 25

x = 155°

Answer:

I think the answer is 10 hours

the 11.95 seems wrong

Step-by-step explanation:

[tex]\frac{1}{6} + \frac{1}{y} = \frac{1}{3.75}[/tex]

multiply by 22.5 y

3.75 y + 22.5 = 6y

y = 10

after each year it's 83% of it's value from last year (100%-17%=83%)

the function in 19000 * (0.83) ^x

3 will be filled in for x

19000 * (0.83) ^3= 10863.953

$10863.95

Answer:

$10,863.95

Step-by-step explanation:

y = 19,000[tex](.83)^{t}[/tex]

y = 19,000[tex](.83)^{3}[/tex]

y =$10,863.95

The image of this question is missing and so i have attached it.

Answer:

dd/dt = 4.47 ft/s

Step-by-step explanation:

From the image attached, let's denote the following;

d = horizontal distance beneath pulley

h = height of pulley

l = diagonal from the pulley to the head of the person

v = velocity of rope rising

Using pythagoras theorem;

l² = d² + h²

Differentiating with respect to time and considering h = c^(te) gives;

2l(dl/dt) = 2d(dd/dt)

We are given;

d = 20 ft

h = 10 ft

v = 4 ft/s

We know that velocity in this case is change in diagonal distance with time. Thus;

v = dl/dt = 4 ft/s

From earlier, we saw that;

2l(dl/dt) = 2d(dd/dt)

Thus, reducing it gives

(dl/dt)(l/d) = dd/dt

Now, l² = d² + h²

l = √(d² + h²)

Also, v = dl/dt = 4

Thus;

4(√(d² + h²))/d = dd/dt

4(√(20² + 10²))/20 = dd/dt

dd/dt = 4.47 ft/s

Answer:

[tex] \frac{1}{6} [/tex]

Step-by-step explanation:

[tex] \frac{7}{5} \times \frac{5}{12} - \frac{3}{12} \times \frac{7}{5} - \frac{1}{15} = \frac{7}{5} ( \frac{5}{12} - \frac{3}{12} ) - \frac{1}{15} = \frac{7}{5} \times \frac{1}{6} - \frac{1}{15} = \frac{7}{30} - \frac{2}{30} = \frac{5}{30} = \frac{1}{6} [/tex]

Answer:

C.

0.5; 13.5; 1093.5

Step-by-step explanation:

Answer:

a) 30

b)600pi

Step-by-step explanation:

For the first questions, since the arc is 240°, the area of the sector and circumference will be 240/360 or 2/3 of the total of the circles'. Therefore 125.6 x 3/2 is the circumference, which is 188.4. When we divide this by 6.28, we get 30

Now, since the area is pi r^2 where we know that r=30, we get 900pi as the area of the whole thing, however since the sector is 2/3 of the whole circle, 2/3 x 900pi = 600pi

Answer:

hope this help

Step-by-step explanation:

Answer:

90

51

10

Step-by-step explanation:

Answer:

Step-by-step explanation: you have to ask your parents for help

Answer:  True

Explanation:

Consider a 3D cardboard box that you can unfold. It would unfold into a 2D net that you can then re-fold back into its 3D form. The 2D net is useful to help visualize and calculate the surface area. The surface area is simply the total area of all the external faces.

Answer:

The orginal number is 26.

Step-by-step explanation:

So the units digit can be 3 6 or 9

The tens digit can be 1 2 or 3

So the original number can be 13

31 = 2*13+ (1+3) + 2

31 =? 26 + 4 + 2    

This doesn't work. The right side is 32

26

62 = 2*26 + 8 + 2

62 = 52 + 8 + 2

This is your answer.

3 and 9 won't work because 39 is odd and so is 93. The result has to be even.

Answer:

1, 50

2, 25

5, 10

10, 5

25, 2

Answer:

Step-by-step explanation:

V  W  

1 x 50     = 50

1.5 x 33 1/3 = 50

2 x 25     = 50

2.5 x 20     = 50

3 x 16 2/3 = 50

3.5 x 14 2/7 = 50

4 x 12 1/2 = 50

4.5 x 11 1/9 = 50

5 x 10     = 50

5.5 x 9     = 50

6 x 8 1/3 = 50

6.5 x 7 2/3 = 50

7 x 7 1/7 = 50

7.5 x 6 2/3 = 50

8 x 6 1/4 = 50

8.5 x 5 8/9 = 50

9 x 5 5/9 = 50

9.5 x 5 1/4 = 50

10 x 5     = 50

10.5 x 4 3/4 = 50

11 x 4 5/9 = 50

11.5 x 4 1/3 = 50

12 x 4 1/6 = 50

12.5 x 4     = 50

13 x 3 6/7 = 50

13.5 x 3 5/7 = 50

14 x 3 4/7 = 50

Answer:

4 to 3

Step-by-step explanation:

The ratio of salt to pepper is

2/3 to 1/2

Multiply both fractions by 6

6 * 2/3 to 6 * 1/2

4 to 3

Answer:

$61.50

Step-by-step explanation:

14.25(4) + 4.50

= 57.00 + 4.50

= 61.50

Answer:

Option B

a(n) = 8 + (n-1) • 6

Answered by GAUTHMATH

Answer:

[tex]Expected = 0.09375[/tex]

Step-by-step explanation:

Given

[tex]Balls = 4[/tex]

[tex]n = 4[/tex] --- selection

Required

The expected distinct colored balls

The probability of selecting one of the 4 balls is:

[tex]P = \frac{1}{4}[/tex]

The probability of selecting different balls in each selection is:

[tex]Pr = (\frac{1}{4})^n[/tex]

Substitute 4 for n

[tex]Pr = (\frac{1}{4})^4[/tex]

[tex]Pr = \frac{1}{256}[/tex]

The number of arrangement of the 4 balls is:

[tex]Arrangement = 4![/tex]

So, we have:

[tex]Arrangement = 4*3*2*1[/tex]

[tex]Arrangement = 24[/tex]

The expected number of distinct color is:

[tex]Expected = Arrangement * Pr[/tex]

[tex]Expected = 24 * \frac{1}{256}[/tex]

[tex]Expected = \frac{3}{32}[/tex]

[tex]Expected = 0.09375[/tex]

Answer:

16

Step-by-step explanation:

the quadratic equation –3 = –x2 + 2x can be changed into :

x²-2x-3= 0

a=1, b= -2 , and c = -3

so, the discriminant = (-2)²-4(1)(-3)

= 4 + 12 = 16

Answer:

[tex]=\frac{1}{8568}\ = .00011\\\ =\frac{7}{8568} = .00081[/tex]

Step-by-step explanation:

[tex]5/18\cdot \:4/17\cdot \:3/16\cdot \:2/15\cdot \:1/14=\frac{1}{8568}[/tex]

Answer:

(6) the letter n : intersection which means the number you will find at the first bracket and has the same number at the other bracket

9 in 8956 = 900

9 in 95675 = 90000

9 = 9 in 124569

9 in 68795 = 90

90000 = 9 in 2549652.........

hope it helps...

Answer: [tex]\dfrac{8}{3}\ m[/tex]

Step-by-step explanation:

Given

Length of the plank is [tex]6\ m[/tex]

Foot of the flank is [tex]4\ m[/tex] away from the wall

Lizard climbs 2 m up the wall

from the figure, the two triangles are similar

[tex]\therefore \dfrac{2}{6}=\dfrac{x}{4}\\\\\Rightarrow x=4\times \dfrac{2}{6}\\\\\Rightarrow x=\dfrac{4}{3}\ m[/tex]

So, the distance from the wall is

[tex]\Rightarrow 4-x\\\\\Rightarrow 4-\dfrac{4}{3}\\\\\Rightarrow \dfrac{8}{3}\ m[/tex]

Answer:

≈ 0.19

Step-by-step explanation:

So first, we find the probability of getting 1 yellow marble (the formula is the number of amount of type over the total number of items), which is:

10/(6+10+5+1)

= 10/22

= 5/11.

So getting a yellow marble on the first try is 5/11 likeliness.

Now, for the second one, we do the same except that you are NOT putting it back into the bag, which means we have to subtract the yellow marble you already took AND ALSO ONE FROM THE TOTAL AMOUNT OF YELLOW MARBLES.

To find the probability of getting the second marble, our equation is:

9/(6+9+5+1)

= 9/21

= 3/7.

Lastly, to find the probability of getting them both consecutively, we multiply the two results.

5/11 * 3/7

= 15/77

≈ 0.19

I hope this helped! :D

Add the ratio: 3 + 5 = 8

Divide total students by that:

32/8 = 4

The ratio for girls is 3, multiply the 4 by 3:

4 x 3 = 12

There are 12 girls

Answer:

12

Step-by-step explanation:

If the ratio of girls to boys is 3:5, that means that for every 8 total students, 3 would be girls and 5 would be boys. Therefore 3/8 of the students are girls and 5/8 are boys. If 3/8 are girls, then:

[tex]\frac{3}{8}[/tex] of 32

= [tex]\frac{3}{8} * 32[/tex]

[tex]=\frac{3 * 32}{8} \\= \frac{96}{8} \\= 12[/tex]

There are 12 girls.

Answer: C=10.99

Step-by-step explanation: