Question

Tia photocopied the image of a design for a monorail track system. The figure below shows the design and its photocopy.

The ratio of DA : CD is 2 : 3. The total length of track on the design is 46 meters. What is the length, in meters, of side EH on the photocopied image?

Answer 1

I know AD is 7
DC is 15
BC is 14
and AB is 17

I just don't understand how to use the ratios in order to get EH

Answer 2

@ivanmlerner @austinL @AustinM

Answer 3

I have no Idea SORRY

Answer 4

Hmm... Do you know anyone who does?

Answer 5

@electrokid

Answer 6

Im not sure Ill see Tho

Answer 7

The lenghts you already have, are they given to you?

Answer 8

No, I found them. The only ones given to me are AB 17 and BC 14

Answer 9

So the numbers you found are probably wrong, what that ratio means is that if AD has lenght 2, CD must have lenght 3, and if you change one of them the other changes proportionaly. Therefore, when you take the value of AD and divides by the value of CD it must give you 2/3, and that is not what happens with your numbers

Answer 10

No. Like 2 is for design and 3 is for photocopy.

Answer 11

@satellite73

Answer 12

This cannot be, because it says its the ratio of DA : CD and both are on the design

Answer 13

Then I don't know...

Answer 14

I guess what it wants you to do is to, since it does not give you any information about the photocopy, find AD and then say that EH has the same lenght as AD because both drawings seem to be of the same size

Answer 15

Like 46-17-14= 15.

So some how that 15 needs to make up for AD and DC. But I know that

AD<DC<AB<BC

AD has the smallest number and its ratio is 2
DC has the second smallest number but is greater than AD but smaller than AB. Its ratio is 3.

Answer 16

Actually what the ratio means is that if you divide one by another it gives you 2/3 so you cant say that AD has ratio 2 because the ratio is a correlation between two numbers, in this case AD and CD. What you need to do here is to change those words into mathematical formulas: since 15 makes up for AD and CD\[AD+CD=15\]Since their ratio is 2/3\[\frac{AD}{CD}=\frac{2}{3}\]...\[AD+CD=15\]\[3AD-2CD=0\]

Answer 17

Now you need to solve the system

Answer 18

By any chance is it possible that...
AD is 5 and DC is 10?

Answer 19

5+10=15
15-20= -5

Answer 20

its not guessing, you need to isolate one of them on one of the formulas and then substitute on the other, like that:\[AD+CD=15\]\[AD=15-CD\]Substitute on the second:\[3AD-2CD=0\]\[3(15-CD)-2CD=0\]\[45-3CD-2CD=0\]\[5CD=45\]\[CD=9\]Now substitute again on any formula:\[9+AD=15\]\[AD=6\]

Answer 21

It can't be like that though, because 5CD doesn't equal 9, because 46/9, is a decimal

Answer 22

@ivanmlerner

Answer 23

But, I guess it works too. Okay, then you deserve your badge. yey

Answer 24

Sorry, I left for a while
I didn't understood you doubt in case you still have it