Question 153916
The probability of the dart landing in the yellow region is simply the ratio of the area of the yellow region to the total area of the entire figure. 
First, you need to find the total area of the entire figure. Since they are all squares, the area is found by squaring the given dimension.
{{{3^2 = 9}}} sq.in.
{{{6^2 = 36}}}sq,in.
{{{9^2 = 81}}}sq.in.
{{{12^2 = 144}}}sq.in.
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Total area = the sum of the individual areas.
A = 270 sq.in.
The area of the yellow square is {{{9^2 = 81}}} sq.in.
The ratio is: {{{81/270}}} Simplify this to {{{3/10 = 0.3}}}
The probability of the dart landing in the yellow region is 0.3 or 30%