Question

A design on the surface of a balloon is 9 cm wide when the balloon holds 62 cm3 of air. How much air does the balloon hold when the design is 18 cm wide?

496 cm3
124 cm3
407 cm3
248 cm3
@amistre64

Answer 1

kind of an assumptious question

what our scalar?

Answer 2

9 times what, is 18?

Answer 3

2

Answer 4

this is important to the solution, how does the linear scalar effect volume?

Answer 5

so then you would times 62 by 2

Answer 6

what is the formula for the volume of a sphere?

Answer 7

4rsquared pi

Answer 8

no, volume ....

Answer 9

area is squared (2 dimensions), volume is cubic (3 dimensions)

Answer 10

4
3πrcubed

Answer 11

good, 4/3 pi r^3

r is a linear measure, radius. a scale by 2 gives us 2r

Vnew = 4/3 pi (2r)^3

or written another way

Vnew = 4/3 pi r^3 (2)^3

Vnew = Vold (2)^3

Answer 12

so what would i do next

Answer 13

the calculation of course ....

Answer 14

how much bigger is the new volume when we have a linear scalar value of 2?

Answer 15

2

Answer 16

no, thats not what i wrote at all ....

Answer 17

8?

Answer 18

Vold = 4/3 pi r^3

r is a linear measure, radius. a scale by 2 gives us 2r

Vnew = 4/3 pi (2r)^3

or written another way

Vnew = 4/3 pi r^3 (2)^3

Vnew = Vold (2)^3

Answer 19

2 x 2 x 2

Answer 20

yeah, 2^3 = 8

Answer 21

oh good, it looks like the posts are getting jumbled about .... site might go down soon

Answer 22

what

Answer 23

the posts arent in order on my end ....

Answer 24

old volume * 8 = new stuff

Answer 25

o i got 496 for the new volume is that right?

Answer 26

?

Answer 27

Sorry to interupt guys but @amistre64 i need you to check something super super fast someone is testing my knowledge and i dont like it

Answer 28

@amistre64

Answer 29

62*8 is correct

Answer 30

The volumes of two similar solids are 1331 m3 and 343 m3. The surface area of the larger one is 484 m2. What is the surface area of the smaller one?

196 m2
343 m2
1372 m2
none of these
@amistre64

Answer 31

@Here_to_Help15

Answer 32

ok Thanks @amistre64

Answer 33

Ratio of the volumes is 1331/343 = 3.880

linear dimensions are proportional to the of that, and area is proportional to the square of the linear dimension, so over all, it is an exponent of 2/3

so 3.880^(2/3) = 2.469

so dividing 484 / 2.469, we get 196 m^2

Answer 34

In that space i left open this goes there one sec

Answer 35

what are we trying to figure out ?

Answer 36

so what would it be

Answer 37

@Here_to_Help15

Answer 38

I told you @18jonea look at what i wrote

Answer 39

o sorry so oits 196m squared

Answer 40

mhmm

Answer 41

o sorry so oits 196m squared