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3 years ago

Can someone please explain the math on this one to me? Thanks!

Mathematics

2 answers:

kodGreya [7K]3 years ago

8 0

Answer:

18 men = 36 tons in 6 hours

Step-by-step explanation:

3 men = 1 ton in 1 hour

6 men = 2 ton in 1 hour

9 men = 3 tons in 1 hour

with this you find a pattern

3 men = 2 tons in 2 hours

3 men = 3 tons in 3 hours

3 men = 6 tons in 6 hours

6 men = 12 tons in 6 hours

9 men = 18 tons in 6 hours

12 men = 24 tons in 6 hours

15 men = 30 tons in 6 hours

18 men = 36 tons in 6 hours

(This is how i worked it out)

shutvik [7]3 years ago

6 0

Answer:

18 people

Step-by-step explanation:

Method A:

3 man-hours to stack 1 ton

36 tons is 36 times 1 ton, so it takes 36 times as long to stack.

36 * 3 man-hours to stack 36 * 1 ton, or

108 man-hours to stack 36 tons

To do the job in 6 hours instead of 108, you need to do 108/6 = 18 times as much work per hour, so you need 18 times as many people.

18 * 1 person = 18 people

Answer: 18 people

Method B:

1 person works 3 hours and stacks 1 ton. That same person works another 3 hours and stacks another ton. In a total of 6 hours, 1 person stacked 2 tons. Since you need 36 tons stacked in the same 6 hours, and 36 = 18 * 2, you need 18 times the number of people, so you need 18 people.

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1) through: (-2,4), slope = 0<br> how you do this??

elena-s [515]

Answer:

y = 4

Step-by-step explanation:

I assume you want to find the slope-intercept form of the given information.

We are given the slope and a point, so we can find the y-intercept.

y = 0x + b

4 = 0(-2) + b

4 = 0 + b

4 = b

Put everything we know/solved for back into the formula [ y = mx + b ]

y = 4

Best of Luck!

5 0

2 years ago

It will take Adam four hours to drive to Disney Park, and 2.5 times less time if driving 45 mph faster. What is the distance Ada

Mashcka [7]

<h2>Hello!</h2>

The answer is:

The distance to over by Adam to get to the park is 108 miles.

To solve the problem, we need to write two equations using he given information about the times and his speed.

So,

For the first equation we have: Travel to Disney Park

$time=4hours$

$Distance=v*4hours$

For the second equation we have: Travel back from Disnery Park

$time=4hours-2.5hours=1.5hours$

$Speed=v+45mph$

$Distance=(v+45mph)*1.5hours$

Then, if Adam covered the same distance going and coming back, we have:

$v*4hours=(v+45mph)*1.5hours$

$v*4hours=v*1.5hours+45mph*1.5hours$

$v*4hours-v*1.5hours=45mph*1.5hours$

$v*2.5hours=67.5miles$

$v=\frac{67.5miles}{2.5hours}=27\frac{miles}{hour}=27mph$

We have that the speed when he was going to Disney Park was 27 mph.

Now, to calculate the distance, we need to substitute the obtained speed in any of the two first equations.

Therefore, substituting the speed into the second equation, we have:

$Distance=(v+45mph)*1.5hours$

$Distance=(27mph+45mph)*1.5hours=72mph*1.5hours=108miles$

Hence, we have that the distance that Adam should cover to get to the park is 108 miles.

Havea nice day!

8 0

3 years ago

An open top box is to be built with a rectangular base whose length is twice its width and with a volume of 36 ft 3 . Find the d

denpristay [2]

Answer:

The dimensions of the box that minimize the materials used is $6\times 3\times 2\ ft$

Step-by-step explanation:

Given : An open top box is to be built with a rectangular base whose length is twice its width and with a volume of 36 ft³.

To find : The dimensions of the box that minimize the materials used ?

Solution :

An open top box is to be built with a rectangular base whose length is twice its width.

Here, width = w

Length = 2w

Height = h

The volume of the box V=36 ft³

i.e. $w\times 2w\times h=36$

$h=\frac{18}{w^2}$

The equation form when top is open,

$f(w)=2w^2+2wh+2(2w)h$

Substitute the value of h,

$f(w)=2w^2+2w(\frac{18}{w^2})+2(2w)(\frac{18}{w^2})$

$f(w)=2w^2+\frac{36}{w}+\frac{72}{w}$

$f(w)=2w^2+\frac{108}{w}$

Derivate w.r.t 'w',

$f'(w)=4w-\frac{108}{w^2}$

For critical point put it to zero,

$4w-\frac{108}{w^2}=0$

$4w=\frac{108}{w^2}$

$w^3=27$

$w^3=3^3$

$w=3$

Derivate the function again w.r.t 'w',

$f''(w)=4+\frac{216}{w^3}$

For w=3, $f''(3)=4+\frac{216}{3^3}=12 >0$

So, it is minimum at w=3.

Now, the dimensions of the box is

Width = 3 ft.

Length = 2(3)= 6 ft

Height = $\frac{18}{3^2}=2\ ft$

Therefore, the dimensions of the box that minimize the materials used is $6\times 3\times 2\ ft$

4 0

3 years ago

Just answer 3 and 4 you don’t need to show your work just answers please!

ad-work [718]

#3.) 48 pieces of ribbon
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8 0

2 years ago

The net of a pyramid is shown below. The surface area of the solid is ____ square inches.

Effectus [21]

Area of a triangle= bh/2b=4in h=8in8x4/2=16in
there are 4 triangles
4x16=64
area of a rectangle=bh
4x4=16
64+16=80in^2

5 0

3 years ago

Read 2 more answers