All categories

3 years ago

Pls answer Question 28 and 29 asap.

Mathematics

1 answer:

Kaylis [27]3 years ago

4 0

28. Answer: 86% decrease

Step-by-step explanation:

Original Sphere has a radius of 100% → r =1

Surface Area of Original Sphere:

S.A. = 4πr²

= 4π(1)²

= 4π

New Sphere has a diameter of 75% → d = 0.75 → r = 0.375

Surface Area of New Sphere:

S.A. = 4πr²

= 4π(0.375)²

= 0.5625π

$\text{\% Change} =\dfrac{New - Original}{Original}\\\\.\qquad \qquad =\dfrac{0.5625\pi -4\pi}{4\pi}\\\\.\qquad \qquad =\dfrac{-3.4375\pi}{4\pi}\\\\.\qquad \qquad =-0.86$

The negative sign represents a decrease.

*********************************************************************************

29. Answer: 72 bottles

Step-by-step explanation:

Volume of a hemisphere is:

$V=\dfrac{2}{3}\pi r^3\\\\.\quad =\dfrac{2}{3}\pi (18)^3\\\\.\quad = 3888\pi$

Volume of a cylinder is:

$V=\pi r^2h\\\\.\quad =\pi (3)^2(6)\\\\.\quad =54\pi$

The number of cylinders needed is:

$\dfrac{3888\pi}{54\pi} = 72$

You might be interested in

I NEED YOUR HELP PLEASE GRADES ARE DUE TODAY AND I DONT KNOW HOW TO DO THIS.

lawyer [7]

Answer:

#1 c. -1

#2 b. 1 is less than or equal to x which is less than or equal to three

#3 a. 37.5 is less than or equal to y which is less than or equal to 87.5

#4 b. 3

#5 b. (2, 3, 4, 5, 6)

#6 d. (45, 55, 65, 75, 85)

Step-by-step explanation:

Domain is the x value and y is the range. For #1 the answer is c because you can't go golfing for -1 hours. For #2, the answer is b because they are all the acceptable values for the domain which is represented by x and x is the time spent at the golfing bay. The answer would not be c because you could go to the bay for 2.75 hours it doesn't have to be just 1, 2, 3. For #3 the concept is similar because the range aka total cost can be all the values in between 37.5 and 87.5. For #4 a reasonable domain value which is number of people is 3 because you can't have 2.5 people and you can't have -4 people and thus all of the above isn't possible leaving three. #5 is b because you can only have those set numbers to represent people. If you chose a that would mean you could have 1.5 people which isn't possible thus only numbers 2, 3, 4, 5, and 6 are possible. For #6 The answer is d because when you plug in numbers 2, 3, 4, 5, 6 into the x value one at a time and solve the equation, those numbers equal t. Just use your basic knowledge to figure these out there isn't much math you just have to know that domain means x and range means y. y is 9/10 always by itself on one side of the equal sign. When in doubt think, can I have a half a person. Think of the real world and apply to math. Goof luck on future problems!

7 0

3 years ago

What is 10 x 6 please answer assap

rosijanka [135]

60 that's the answer.

7 0

3 years ago

Need help with math

Len [333]

2) no solution

3) x=3

8 0

3 years ago

Frodo ran miles in of an hour. How many miles can Frodo run in one hour?

GaryK [48]

Frodo can run 1 miles in 1 hour

4 0

3 years ago

An experienced carpenter can frame a house twice as fast as an apprentice. Working together, it takes the carpenters 2 days. How

AleksAgata [21]

Answer:

6 days

Step-by-step explanation:

Let the time taken by Carpenter working alone = $C$ days

Then time taken by apprentice alone = Twice as that of taken by Carpenter = 2 $C$ days

Time taken working together = 2 days

Work done in one day working together = $\frac{1}{2}$

Work done in one day by Carpenter working alone = $\frac{1}{C}$

Work done in one day by apprentice working alone = $\frac{1}{2C}$

Work done in one day by Carpenter working alone + Work done in one day by Carpenter working alone = $\frac{1}{C}$ + $\frac{1}{2C}$ = Work done in one day working together = $\frac{1}{2}$

$\dfrac{1}{C}+\dfrac{1}{2C}=\dfrac{1}{2}\\\Rightarrow \dfrac{2+1}{2C}=\dfrac{1}{2}\\\Rightarrow C = 3\ days$

Time taken by Carpenter alone to complete the work = 3 days

Time taken by Apprentice alone to complete the work = 3 $\times$ 2= 6 days

4 0

3 years ago