Question

can someone tell me the dilation (scale factor) and the ratio?

http://prnt.sc/dg428a

(2 two first constructions are from the same object and then the other two are from another object)

Answer 1

Show ratios of corresponding sides.

Answer 2

i need to find ratios

Answer 3

Yes. Ratios. First, find corresponding sides.

Don't take the shortest side of the small drawing and compare it to the largest side of the big drawing. Identify sides that correspond in the two drawings.

Answer 4

well the top correspond and so do the bottom and the sides correspond on the larger sides correspond

Answer 5

62 inches = 7 1.2 inches
26 1/2 = 5 inches
7 1/2 = 9 1/2 inches
26 1/2 inches = 1 1/2 inches

Answer 6

Now, try the ratios.

62 / 7.5
26.5 / 5

Do they make sense?

Answer 7

i don't think so @tkhunny

Answer 8

If you are SURE you have a handle on "corresponding", then we are done.

I see these corresponding parts

62 / 7.5 = 8.266666
26.5 / 1.5 = 17.3333333
and
19.5 / 5 = 3.9
26.5 / 7.5 = 3.5333

There are not very many choices from here:
1) Drawings are really bad.
2) We're just not finding any corresponding parts.
3) We have parts of two different drawings.

Answer 9

@tkhunny they are different objects.. i mean they are similar in rectangle shape but the sides are different.
62 / 7.5 is a ratio?
im slightly confused on how to find the scale factor

Answer 10

Okay, let's try this:

On the paper, 32 Horizontal Blocks = 8.5" ==> 1 Block = 0.265625"

62" ==> 22 Blocks ==> 22*0.265625" = 5.84375" ==> Ratio = 1/10.610
26.5" ==> 10 Blocks ==> 10*0.265625" = 2.658625" ==> Ratio = 1/9.968
19.5" ==> 8 Blocks ==> 8*0.265625" = 2.125" ==> Ratio = 1/9.176

It looks like it's a GOOD scaling, but not a great scaling.
If it were a perfect scaling, those ratios would be the same.

Answer 11

when I was drawing it.. I didn't count the boxes I just drew rectangles. @tkhunny

Answer 12

Well, there you go. We're close, then.

Answer 13

how would we find the ratios then? @tkhunny

Answer 14

If you have a real object, you don't FIND the ratios, you MAKE them. What ratio do you want? If you already drew the figure, and you have discovered that different parts have been scaled differently, you should enjoy your new object that is NOT a scale model of the original.

Answer 15

in my assignment it says "Determine the ratio between the object and your replica or model."

Answer 16

Okay, then you should PICK a ratio and then draw it. We have demonstrated clearly that your scaling could use a little help. That's where we are. Until you get those ratios the same, then it is not a proper scaling.

Answer 17

@tkhunny im not sure how to pick a ratio.. you mean like 1:2? can it just be anything?

Answer 18

Look at your object. Say, 12 ft x 10 ft x 4 ft
Look at your paper. Say, 8½ in x 11 in.

Think on the orientation. Looks like Landscape might be more convenient.

You must cram 12 ft into 10 in. This is a ratio of 14.4
You must cram 10 ft into 8½ in. This is a ratio of 14.1
Now, those ratios are just BARELY fitting on your paper. You must now be reasonable.

Pick greater ratio If you pick the lesser, one direction will spill off the page.

Okay, so 14.4.

Think about your margins. Do you REALLY have all the way to the edge of the paper? Probably not. Make the ratio larger to allow for margins.

Okay, so 15? That makes the 12 ft side now 9.6 in, leaving more than an inch on each side.

Okay, now decide how you want to display the 3rd dimension. 4 ft, with a 30º perspective drawing, will take another 3.7 inches one way and 1.8 in the other way. We'll have to shrink more!!

Ask yourself. What do I want to do? How much do I have to shrink to make it happen?

Maybe you don't want a perspective drawing. Put one view in portrait at the top of the page and the end view at the bottom. Make it work!

Answer 19

ok so the ratio would be between 14.4 and 15? @tkhunny

Answer 20

that would make scale factor .25? or something like that?

Answer 21

I would guess more than 15, depending on what YOU want to do.

Answer 22

Scale factor of 15 takes 15 in down to 1 in. ==> 0.0666666666