How do I evaluate ⌈10⌉ ????

Mr. Kohl has a breaker containing n milliliters of solution to distribute to the students in his chemistry class. If he gives ea

77julia77 [94]

Answer:

There were 26 students in his class and the teacher had 83 ml of the solution.

Step-by-step explanation:

Mr. Kohl has a "x" amount of solution, if he divides it by the number of students "n" he'll give each student 3 milliliters and have a left over of 5 milliliters. If the amount of solution Mr. Kohl had was "x + 21" then he'd be able to give each student 4 milliliters of the solution. From these informations we have:

x = 3*n + 5

(x + 21)/n = 4

x + 21 = 4*n

x = 4*n - 21

Now that we have two equations and two variables we can solve the system of equations, as seen bellow:

3*n + 5 = 4*n - 21

3*n - 4*n = -21 - 5

-n = -26

n = 26

x = 4*26 - 21 = 83 ml

There were 26 students in his class and the teacher had 83 ml of the solution.

3 0

3 years ago

The perimeter of an equilateral triangle is 63 inches. If the length of each side is (4x-3), find the value of x.

balu736 [363]

Equilateral triangle have the same side lengths. Perimeter = sum of all sides
(4x - 3) + (4x - 3) + (4x - 3) = 63
Remove parentheses
4x - 3 + 4x - 3 + 4x - 3 = 63
Combine like terms
12x - 9 = 63
12x = 72, x = 6

Solution: x = 6

4 0

3 years ago

5/6 is equivalent to a percent that is larger than 100%. <br><br> True or False<br><br> 13 pts.

omeli [17]

I think it's false.... 5/6 is 83.33% as a percent so I don't think it's true.

8 0

3 years ago

Read 2 more answers

Let A be a set of numbers.

LUCKY_DIMON [66]

Answer:

a. closed under addition and multiplication

b. not closed under addition but closed under multiplication.

c. not closed under addition and multiplication

d. closed under addition and multiplication

e. not closed under addition but closed under multiplication

Step-by-step explanation:

a.

Let A be a set of all integers divisible by 5.

Let $x,y$ ∈A such that $x=5m\,,\,y=5n$

Find $x+y,xy$

$x+y=5m+5n=5(m+n)$

So, $x+y$ is divisible by 5.

$xy=(5m)(5n)=25mn=5(5mn)$

So,

$xy$ is divisible by 5.

Therefore, A is closed under addition and multiplication.

b.

Let A = { 2n +1 | n ∈ Z}

Let $x,y$ ∈A such that $x=2m+1\,,\,y=2n+1$ where m, n ∈ Z.

Find $x+y,xy$

$x+y=2m+1+2n+1=2m+2n+2=2(m+n+1)$

So,

$x+y$ ∉ A

$xy=(2m+1)(2n+1)=4mn+2m+2n+1=2(2mn+m+n)+1$

So,

$xy$ ∈ A

Therefore, A is not closed under addition but A is closed under multiplication.

c.

$Let A=\{2,5,8,11,14,...\}$

Let $x=2,y=5$ but $x+y=2+5=7$ ∉A

Also,

$xy=2(5)=10$ ∉A

Therefore, A is not closed under addition and multiplication.

d.

Let A = { 17n: n∈Z}

Let $x,y$ ∈ A such that $x=17n,y=17m$

Find x + y and xy

$x+y=17n+17m=17(n+m)$

$xy=(17m)(17n)=289mn=17(17mn)$

So,

$x+y,xy$ ∈ A

Therefore, A is closed under addition and multiplication.

e.

Let A be the set of nonzero real numbers.

Let $x,y$ ∈ A such that $x=-1,y=1$

Find x + y

$x+y=-1+1=0$

So,

$x+y$ ∈ A

Also, if x and y are two nonzero real numbers then xy is also a non-zero real number.

Therefore, A is not closed under addition but A is closed under multiplication.

4 0

3 years ago

68.64 divided by 2.4 SHOW WORK PLEASE

34kurt

Answer:28.6

I started by seeing how many 2.4 can go into 68.64. I found that it is pretty easy to find that if you multiply the 2.4 by ten you get 24 so we do that twice and have 48. We then subtract 48 from the 68.64 which leaves us with 20.64. If we multiply 2.4 by 5 we get 12 so once again subtract 12 from that 20.64 and now we are left with 8.64. So now we need to figure out how many more 2.4 are left well it is more than three because three gives us 7.2 so let’s subtract that from it now we are left with 1.44. Now we need to find out what times 2.4 gives us 1.44. Well it would be .6. So now if we add up everything we get the answer of 28.6. Sorry if this very complicated

7 0

4 years ago