Answer:
<u>12.2</u>
Step-by-step explanation:
100 - 20% = 80%, 80% - 5 = -42, -42 - 8 = <u>-12.2</u>
Answer:
The probability is 
Step-by-step explanation:
We can divide the amount of favourable cases by the total amount of cases.
The total amount of cases is the total amount of ways to put 8 rooks on a chessboard. Since a chessboard has 64 squares, this number is the combinatorial number of 64 with 8,
For a favourable case, you need one rook on each column, and for each column the correspondent rook should be in a diferent row than the rest of the rooks. A favourable case can be represented by a bijective function
with A = {1,2,3,4,5,6,7,8}. f(i) = j represents that the rook located in the column i is located in the row j.
Thus, the total of favourable cases is equal to the total amount of bijective functions between a set of 8 elements. This amount is 8!, because we have 8 possibilities for the first column, 7 for the second one, 6 on the third one, and so on.
We can conclude that the probability for 8 rooks not being able to capture themselves is

You have to remember P.E.M.D.A.S. when doing problems like this.
Drew used PEMDAS so we know he isn't wrong. However, Sam didn't use PEMDAS. She multiplied 2&5 instead of raising 5 to the second.
The correct answer for Sams' problem would be 30.
Hope this helps! :)
Ratio of the free throws completed to attempted free throws is given to be 4:7. This ratio should be equal to the ratio of the next case. Let x be the number of free throws attempted. The proportion takes a form of,
(4 completed / 7 attempted) = (12 completed / x attempted)
Solving for x gives x = 21. Thus, the answer is letter c. which is the second among the choices.
(10x5)+(10x14)+(10x-3)
50+140-30
160