Hi,

I need some help with a question on ratio.

Please see the question in the attached pdf file

Thanks!

For this question you can use a combination of [b]Repeated Identity[b] and Unchanged Total

Chris,

1. Can you elaborate a bit more about unchanged total?

2. The questions is asking the ratio of unshaded area of C:B:A
In this case, I would think the answer is
Y : W : P
22 : 5 : 12

Thanks once again.

Can you elaborate a bit more about unchanged total?

Unchanged Total is basically making a comparison between the total number of units in one scenario against the total number of units in other such as before and after questions. An example would be where you have two people with 3 and 6 sweets respectively. When A gives B 3 sweets, the total remains unchanged as they are passing the sweets between each other. This Concept can be found in the P4, P5, and P6 books in the +hinkingMath series.

For this question, I use the knowledge that P+Z+X+W is 25units. Therefore I can multiply the ratio Z+P+X+W : X+Y+Z (5:6), by 5 making the ratio 25:30.


The questions is asking the ratio of unshaded area of C:B:A
In this case, I would think the answer is
Y : W : P
22 : 5 : 12

Yes. Correct I have given the shaded areas. I have updated the solution to give the ratio for the unshaded area. Thanks