The probability of obtaining a 1 is 1/13, so the probability of not getting a 1, that is, the probability of getting a ball different from 1, is 1- (1/13)=12/13, which is 0.923
x^( 2a - b ) + ( 2b + c ) + ( 2c + a ) =
x^2a + a + 2b - b + 2c + c =
x^3a - b + 3c
Let's calculate the total cost per year:
6168 + 3280 + 2190 + 1200 = 12,838.
Four years will cost 12838 x 4 = 51,352
Your family will help you out with 17,600, so you will need to pay:
51352 - 17600 = 33,752
I think its 19 1/4
sooo sorry if I am wrong