Ask question

Ask question

All categories

2 years ago

13

Dan, Zack, and Brian were each assigned to give a presentation in Social Studies on Monday. In how many different orders can the

y give their presentations?

1 answer:

olga55 [171]2 years ago

3 0

Dan zack brian
zack dan brian
brian dan zack
zack brian dan
brian zack dan
dan brian zack
6 different orders
Hope this helps!!

You might be interested in

Can somebody please help me out

Alekssandra [29.7K]

Answer:

with what????

8 0

3 years ago

Probability of pulling a green marble out of a bag of coloured marble is 2:5 if you were to pull coloured marbles out of the bag

Slav-nsk [51]

Answer: 171 green marbles

Step-by-step explanation: There are 7 total marbles so 100/7 equals 14.28

Then there is a 2 out of 7 total tries so 14.28 * 2 equals 28.57% chance to get a green marble.

600 * 0.2857 = 171.41 marbles but you cant get half a marble so 171 green marbles.

6 0

3 years ago

For which system of equations is (5, 3) the solution? A. 3x – 2y = 9 3x + 2y = 14 B. x – y = –2 4x – 3y = 11 C. –2x – y = –13 x

Alla [95]

The <u>correct answer</u> is:

D) $\left \{ {{2x-y=7} \atop {2x+7y=31}} \right.$ .

Explanation:

We solve each system to find the correct answer.

<u>For A:</u>
$\left \{ {{3x-2y=9} \atop {3x+2y=14}} \right.$

Since we have the coefficients of both variables the same, we will use <u>elimination </u>to solve this.

Since the coefficients of y are -2 and 2, we can add the equations to solve, since -2+2=0 and cancels the y variable:
$\left \{ {{3x-2y=9} \atop {+(3x+2y=14)}} \right. 
\\
\\6x=23$

Next we divide both sides by 6:
6x/6 = 23/6
x = 23/6

This is <u>not the x-coordinate</u> of the answer we are looking for, so <u>A is not correct</u>.

<u>For B</u>:
$\left \{ {{x-y=-2} \atop {4x-3y=11}} \right.$

For this equation, it will be easier to isolate a variable and use <u>substitution</u>, since the coefficient of both x and y in the first equation is 1:
x-y=-2

Add y to both sides:
x-y+y=-2+y
x=-2+y

We now substitute this in place of x in the second equation:
4x-3y=11
4(-2+y)-3y=11

Using the distributive property, we have:
4(-2)+4(y)-3y=11
-8+4y-3y=11

Combining like terms, we have:
-8+y=11

Add 8 to each side:
-8+y+8=11+8
y=19

This is <u>not the y-coordinate</u> of the answer we're looking for, so <u>B is not correct</u>.

<u>For C</u>:
Since the coefficient of x in the second equation is 1, we will use <u>substitution</u> again.

x+2y=-11

To isolate x, subtract 2y from each side:
x+2y-2y=-11-2y
x=-11-2y

Now substitute this in place of x in the first equation:
-2x-y=-13
-2(-11-2y)-y=-13

Using the distributive property, we have:
-2(-11)-2(-2y)-y=-13
22+4y-y=-13

Combining like terms:
22+3y=-13

Subtract 22 from each side:
22+3y-22=-13-22
3y=-35

Divide both sides by 3:
3y/3 = -35/3
y = -35/3

This is <u>not the y-coordinate</u> of the answer we're looking for, so <u>C is not correct</u>.

<u>For D</u>:
Since the coefficients of x are the same in each equation, we will use <u>elimination</u>. We have 2x in each equation; to eliminate this, we will subtract, since 2x-2x=0:

$\left \{ {{2x-y=7} \atop {-(2x+7y=31)}} \right. 
\\
\\-8y=-24$

Divide both sides by -8:
-8y/-8 = -24/-8
y=3

The y-coordinate is correct; next we check the x-coordinate Substitute the value for y into the first equation:
2x-y=7
2x-3=7

Add 3 to each side:
2x-3+3=7+3
2x=10

Divide each side by 2:
2x/2=10/2
x=5

This gives us the x- and y-coordinate we need, so <u>D is the correct answer</u>.

7 0

3 years ago

If a certain number is multiplied by five, the result is the same as twenty-one plus twice the original number. What is the valu

expeople1 [14]

7
7 times 5 = 35
21 + 14 (7*2) = 35

6 0

3 years ago

Read 2 more answers

Assume Cylinder A and Cone B are the same height and the bases have the same radius. If A has a volume of 18π cm3, what is the v

disa [49]

Answer:

Option A $V_B=19\ cm^3$

Step-by-step explanation:

The volume of a cone is:

$V_B = \pi\frac{hr ^ 2}{3}$

The volume of a cylinder is:

$V_A = \pi(r ^ 2)h$

Both figures have the same height h and the same radius r.

The volume of the cylinder $V_A = 18\pi\ cm ^ 3$

We want to find the volume of the cone.

Then, we find r and h:

$V_A = 18\pi = \pi(r ^ 2)h$

We simplify.

$V_A = 18 = (r ^ 2)h$

Then the product of $(r ^ 2)h = 18$ .

We substitute this in the cone formula and get:

$V_B =\frac{\pi}{3}(18)\\\\V_B = \frac{18}{3}\pi\\\\V_B=19\ cm^3$

8 0

2 years ago

Read 2 more answers