<h3>
Answer: 11/13</h3>
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Explanation:
Add up the four numbers given: 4+8+4+10 = 26 items total
Kick out the 4 black shirts since they are neither blue, nor are they pants.
So we have 26-4 = 22 items that are blue or a pair of pants (or both).
Divide that over the total (26) to get the probability we're after:
22/26 = (11*2)/(13*2) = 11/13
Side note: 11/13 = 0.8462 = 84.62% approximately
Answer:

Try to solve the similtanious equation to find the first term and the common difference, then use that information to figure out the 80th term... Update me if you need further help ...
If the axis is x then you go to y so (6, 5)
Set up a proportion. take 3/6 = 20/x
Cross multiply 3 * x = 6 * 20
Simplify 3x = 120
Divide by 3 x = 40
So the denominator of the bottom fraction is 40