So for this question, it is better to draw a table:

----------------White-----------Blue-----------Total
----------|-------------------|---------------|
Colonial
----------|-------------------|---------------|
Ranch
----------|-------------------|---------------|
Total

Now as we are given that 40 % are colonial, hence 60 % will be a ranch
----------------White-----------Blue-----------Total
----------|-------------------|---------------|
Colonial ----------------------------------------40
----------|-------------------|---------------|
Ranch-------------------------------------------60
----------|-------------------|---------------|
Total--------------------------------------------100

Of the 40 % colonial houses, 25% are white so 25% of 40% = 10%, and 40 % of all houses are white.So ranch and white will be 30%
----------------White-----------Blue------------Total
----------|-------------------|---------------|
Colonial-------10--------------------------------40
----------|-------------------|---------------|
Ranch---------30----------------X---------------60
----------|-------------------|---------------|
Total----------40-----------------60--------------100

The question asks what percent of homes are ranch and blue.So we need the value of X
As we can see 30+X =60, Hence X =30 %.
Answer : B

In percent questions, we can also use 100 as the total number of houses.
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Let the total number of homes be 100.

Colonial: \(\frac{40}{100} * 100 = 40\)

Ranch: \(100 - 40 = 60\)


25% of colonial are white: \(\frac{25}{100} * 40 = 10\)


Total 40% of homes(100) are white: \(\frac{40 }{ 100} * 100 = 40\)

Colonial white: 10

Ranch white: 40 - 10 = 30

Total Ranch: 60

Ranch white: 30

Ranch blue: 60 - 30 = 30

Answer B
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Veritas Prep Official Explanation

To solve, set up your Matrix Box, pick a number of 100, and insert the information, being very careful about the wording:



There are 60 total ranch-style homes, and 30 of those are blue, so the answer is 50%.


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