Oof, this is surely a tough one. But, if I'm looking at this correctly, than I think you were in the right mindset when trying to figure both of them out. Like, for #18, think about the formula; P(B|A) = P(A and B)/P(A). So, based on the question, you can let not rolling a 1 on the blue cube be A, and rolling a 1 on the red cube be B. Now, personally, I prefer using the decimals when heading into the equations, but I'll convert the product into a fraction for the instruction's sake. 0.02777777778 + 0.13888888889 = 1/6. 1/6 ≈ 17.7%. You can do the same for #19, the overall outcome would be 5/6, which would be about 83%. Now, that's just me really attempting my hand at it, I will say, Math is far from my strong suite. But, in all honesty, I really am doing my best to help (and no, it's not because of what you offered, lol, more rather I want to help people who struggle with the same problems I do). Anyways, I hope this helps, and if you need more information, or anything, just let me know! Wish ya the best of luck!! ^u^
