Pretty sure the answer is 29/20 or 1 9/20. You get this by find the common denominator , 60, and then adding the number all together and simplifying
Answer:
P(Y = 0) = 0.09
P(Y = 1) = 0.4
P(Y = 2) = 0.32
P(Y = 3) = 0.19
Step-by-step explanation:
Let the events be:
Wednesday
Thursday
Friday
Saturday
Their corresponding probabilities are

Since
= number of days beyond Wednesday that it takes for both magazines to arrive(so possible
values are 0, 1, 2 or 3)
The possible number of outcomes are therefore 
The values associated for each of the outcomes are as follows:

The probability mass function of
is,
![P(Y = 0) = 0.3(0.3) = 0.09\\P(Y = 1) = P[(W, T) or (T, W) or (T, T)]\\= [0.3(0.4) + 0.3(0.4) + 0.4(0.4)]\\= 0.4\\\\P(Y = 2) = P[(W, F) or (T, F) or (F, W) or (F, T) or (F, F)]\\= [0.3(0.2) + 0.4(0.2) + 0.2(0.3) + 0.2(0.4) + 0.2(0.2)]\\= 0.32\\\\P(Y = 3) = P[(W, S) or (T, S) or (F, S) or (S, W) or (S, T) or (S, F) or (S, S)]\\= [0.3(0.1) + 0.4(0.1) + 0.2(0.1) + 0.1(0.3) 0.1(0.4) + 0.1(0.2) + 0.1(0.1)]\\= 0.19](https://tex.z-dn.net/?f=P%28Y%20%3D%200%29%20%3D%200.3%280.3%29%20%3D%200.09%5C%5CP%28Y%20%3D%201%29%20%3D%20P%5B%28W%2C%20T%29%20or%20%28T%2C%20W%29%20or%20%28T%2C%20T%29%5D%5C%5C%3D%20%5B0.3%280.4%29%20%2B%200.3%280.4%29%20%2B%200.4%280.4%29%5D%5C%5C%3D%200.4%5C%5C%5C%5CP%28Y%20%3D%202%29%20%3D%20P%5B%28W%2C%20F%29%20or%20%28T%2C%20F%29%20or%20%28F%2C%20W%29%20or%20%28F%2C%20T%29%20or%20%28F%2C%20F%29%5D%5C%5C%3D%20%5B0.3%280.2%29%20%2B%200.4%280.2%29%20%2B%200.2%280.3%29%20%2B%200.2%280.4%29%20%2B%200.2%280.2%29%5D%5C%5C%3D%200.32%5C%5C%5C%5CP%28Y%20%3D%203%29%20%3D%20P%5B%28W%2C%20S%29%20or%20%28T%2C%20S%29%20or%20%28F%2C%20S%29%20or%20%28S%2C%20W%29%20or%20%28S%2C%20T%29%20or%20%28S%2C%20F%29%20or%20%28S%2C%20S%29%5D%5C%5C%3D%20%5B0.3%280.1%29%20%2B%200.4%280.1%29%20%2B%200.2%280.1%29%20%2B%200.1%280.3%29%200.1%280.4%29%20%2B%200.1%280.2%29%20%2B%200.1%280.1%29%5D%5C%5C%3D%200.19)
There's a couple ways to do this. These look like special triangles to me. Which should be the 30 60 90 triangle's which have the same ratios for their legs. The legs will always be square root three and one and the hypotenuse of two - I can't see what I'm typing for some reason so I will finish in a comment