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small cubes with edge lengths of 1/4 will be..

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RASTA

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18:26 Uhr, 17.05.2022

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Tag!
Small cubes with edge lenghts of 14 will be packed into the right rectangle prosm. how many small cubes are needed to fill the right rectangular prism

the formula for a right rectangular prism is
A=2 (wl+hl+hw)
can i use this formula

l=412 in
w=5 in

h=314 in

and then plug in the dimensions given and solve for the area?
then see how many cubs of 14 in are needed to fill the area?
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pivot

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18:31 Uhr, 17.05.2022

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Hello,

is there a picture to this exercise? If yes, please attach it.
As far as I see you have to fill the rectangular prism with the cubes. So you need the formula for the volume.

greetings,
pivot
RASTA

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18:45 Uhr, 17.05.2022

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Oh, it is volume then. okay,
V=lwh
V=4125314

925134

Volume =73.133

so now, how doi calculate how many cubas fit in this space?

can i perform division, as in,
73.131/4

is this correct?





20220517_110343_Easy-Resize.com
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pivot

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18:57 Uhr, 17.05.2022

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You approach is too complicated. The length of a cube is 14.

How many cubes fits in a row with a height of 314=134?
How many cubes fits in a row with a length of 5=204?
How many cubes fits in a row with a width of 412=184?

Then use that the volume is V=hlh

>>9/2⋅5⋅13/4

Volume =73.13∈3<<

Here it is better to keep the fractions:
9/2513/4=18/420/413/4

And you can go on to replace the numbers by the corresponding number of cubes.


RASTA

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19:05 Uhr, 17.05.2022

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you wrtoe

412=184 ??????

you meant 92, nicht war?
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pivot

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19:09 Uhr, 17.05.2022

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I've made an edit which refers to your approach. Have a look.

Isn't 18/4=9/2?
RASTA

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19:09 Uhr, 17.05.2022

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and pivot, please, you said my approach was too complicated. but that does not mean it is wrong, or is it?

if it is not?
then, can I divide 73.13 by 14 to get the amount of cubes needed, please, confirm this or deny it, please, before I act on your proposed way.
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pivot

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19:10 Uhr, 17.05.2022

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I've made an edit. Have a look. (18:57)
RASTA

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19:47 Uhr, 17.05.2022

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pivot, I like your approach, this one
how many 14 in cubes fit in a row with a height of 314?

what operation Must I do to solve this?

is it division, like in 134 ÷ 14?


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pivot

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20:04 Uhr, 17.05.2022

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Yes. And 13/4÷1/4=13/4*4/1=134*4

I post a slightly other way, although we are not finished yet with this.

The volume of the small cube with the side length 1/4 is 143

The volume of the big cube is 18/420/413/4=18201343

Therefore 182013 small cubes fit in the big cube.
RASTA

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20:20 Uhr, 17.05.2022

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Allow me to follow your way to the end.

134 ÷ 14=13441=524=13

14 ÷ 5=1451=54=1.2

92 ÷ 14=9241=362=18


so I will add all the results


13+1.2+18=32.20

is this correct, if so, then what is next?

RASTA

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20:34 Uhr, 17.05.2022

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I am missiong something. i am sorry. ich verstehe nicht


RASTA

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20:38 Uhr, 17.05.2022

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you told me miy way was too complicated then you psoted how many 14 in cubes fit in a row with a height of 314= we agreed it was 134

and we did this for the three dimensions

541=20

92 ÷ 14=9241=363=12

so we have 134,20,12,

what do we do with these?. I lost you here.


RASTA

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20:45 Uhr, 17.05.2022

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isn't this way even better?

lets find the volume of the small cube

V=lwh

=141414

164
volume of the smaoll cube 164

let's find the volume of the bigger rectangular prism

V=lwh
V=4125334=6758


now,
6758641=5400
5,400 cubes of 14 in will ft in to the rectangular prism.

Isn't this a better way?
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pivot

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20:48 Uhr, 17.05.2022

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Second line:

You have to divide it always by 1/4 and not the other way round. Thus we have 5&divide;1/4=5*4=20.

The rest is right.

RASTA

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20:56 Uhr, 17.05.2022

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You have to divide it always by 14 and not the other way round. Thus we have 5&divide;1/4=5*4=20.

but pivot doesn't division turns into multiplication ????

as in,

5 ÷ 14 becomes 541 which in the end is the same thing =20
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pivot

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21:08 Uhr, 17.05.2022

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Xes, you're right.
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pivot

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21:25 Uhr, 17.05.2022

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But it is not the same as ¼÷5=1/20.
Frage beantwortet
RASTA

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22:03 Uhr, 17.05.2022

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Alright. Ich jetzt verstehe. thanks, pivot!.