Since this is an isosceles triangle, then the lengths of both legs are equal Therefore, x+1=-x+7 2x=6 x=3 Therefore, the length of the base is: 3x-3=3(3)-3=6 Then your answer is (A)
10% chance of burning out 100-10= 90% chance of not burning out 90% = 0.9 3 lightbulbs 0.9^3 = 0.729 = 72.9% The probability that all 3 lightbulbs stay lit by the end of the month is 72.9%
