Question 1192713
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A = probability of selecting a red button
A = (number of red)/(number total)
A = (4)/(18+10+4)
A = 4/32
A = 1/8


B = probability of selecting a black button, given that event A has occurred (no replacement)
B = (number of black)/(number left after event A happens)
B = (10)/(32-1)
B = 10/31


A*B = probability of getting red, then black (no replacement)
A*B = (1/8)*(10/31)
A*B = (1*10)/(8*31)
A*B = 10/248
A*B = 5/124


Answer: <font color=red>5/124</font>
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