Since she has seven key the probability that the first one will open the door is

if it takes three attempts to open the door,the probability is

if the three attempts would not work
then the probability that the fourth attempt will open the door is

hope this helps
Answer:
5
Step-by-step explanation:
first multiply 3 by 7 as 3x7=21
again find the square of 4 as 4^2=16
finally, subtract 16 from 21 as 21-16= 5
Answer:
$107.38
Step-by-step explanation:
$91 (the price) multiplied by the percentage 18% (91 x 18 = 1630) (1638/100=16.38 [the tip})
$91 (th original price) + 15.38 (the tip) = $108.38 (final price)
Answer:
I believe the answer is x=7
Step-by-step explanation:
<em>3x</em> and<em> 4x-1 </em> are corresponding sides and so are <em>14</em> and <em>18</em>.
You cross multiply with the smaller triangle lengths at the top.
3x/(4x-1)= 14/18
Cross multiply to get
18(3x)= 14(4x-1)
54x=56x-14
Subtract 54x on the other side and add 14 to the other (or subtract 56x to the other side)
you get 14=2x and divide 14 by 2 to get x=7
Answer:
The probability that the outcome is less than 6 is 58.333%.
Step-by-step explanation:
Since a 6-sided die with sides numbered 1 through 6 is tossed, ya penny is then tossed, and if the penny comes up heads, the value of the die is multiplied by 2, but otherwise, the value of the die is left unchanged, to determine what is the probability that the outcome is less than 6 the following calculation must be performed:
(5/6 + 2/6) / 2 = X
(0.8333 + 0.0333) / 2 = X
1.1666666 / 2 = X
0.583333 = X
Therefore, the probability that the outcome is less than 6 is 58.333%.