Answer:
Step-by-step explanation:

Answer: 15 / 56
Step-by-step explanation:
Number of red checkers = 3
Number of black checkers = 5
Total number of checkers = 8
P(black, then red) = 5/8 × 3/7 = 15/56
We should note that the probability to pick a black checker first will be 5 out of 8. Then, there'll be 7 checkers left and the probability to pick a res checker will be 3/7. We then multiply the probabality of each together.
Normally, you would do whatever is inside of the parenthesees first then do the rest but we cant get any further so we remove the parenthasees by distrubtion
7a+6b-4(3a-3b)
-4(3a-3b)
a(b+c)=(ab)+(ac)
-4(3a-3b)=-12a-(-12b)
7a+6b-12a+12b
7a-12a+6b+12b
-5a+18b
that's the asnwer
-5/-7 = 5/7 = 0.71428577142857... The decimal form of the fraction never ends, so 5/7 is not a rational number