Hey the answer to your question is -6.4
Both of them together have 690 because you subtract 152 from 421 so...
421-152=269
Then add 269 to 421
421+269=690
There is a 2 in 4 chance for a red shirt
there is a 1 in 2 chance for blue pants
There is (I think) a 1 in 6 chance for the chosen pain to be worn.
The third term is 9
t(3)=2(3)+3
6+3 = 9