Answer:
answer is 5 this question
The answer to a "sum and difference" problem is that the larger number is the average of those given: (43 +15)/2 = 29.
The smaller number can be computed any of several ways, but subtracting the difference works: 29 -15 = 14
The larger number is 29.
The smaller number is 14.
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You can let the numbers be a and b, and let the sum and difference be s and d. Then you have
.. a + b = s
.. a - b = d
Add these two equations, and you find "b" is eliminated:
.. 2a = s + d
.. a = (s + d)/2 . . . . . . the average of the sum and difference
.. b = a - d . . . . . . . . . from the second equation
This solution is generic. Even if you have to "show work" on such a problem, you can use this known result to check your work.
59 can't go into 9, but if u mean the other way then it is 9.83
Answer:
The value is 
Step-by-step explanation:
From the question we are told that
The number of keys is n
The number of keys remaining after the first key is chosen is n-1
The probability that he gains entrance with the first key he selects is 
Generally the probability that the first key does not open the door is

Generally the number of keys remaining after the second key is chosen is
n-2
Generally the probability that he gains entrance with the second key he selects is

Generally the probability that the second key does not opens the door is

Generally the probability that he gains entrance with the third key he selects is

Generally the probability that the door opens with the third key

=> 
=> 
Note :
All the outcome of the events are independent
72/6+ 85/6
= (72+ 85)/6
= 157/6
= (156+1)/ 6
= 156/6+ 1/6
= 26+ 1/6
= 26 1/6
The final answer is 26 1/6~