Answer: 504
Step-by-step explanation:
When we select r things from n things in a order , we use permutations.
Formula for permutation: 
Given : The number of family members who are potential kidney donors. = 9
Number of people needed to be selected for best match, a second-best match, and a third-best match ( in an order)=3
Then, the number of possible orders are = 

Hence, the number of possible orders 504.
Answer : 1.4 x 10^-9
Step-by-step explanation:
0.0000000014
= 1.4 x 10^-9
A mountaineer climbed 1000 feet at a rate of x feet/hour
1000 = x ( t 1 ) eq1
5000 = X ( t 2) eq2 ( he climbed additional at different rate )
the rate was 10 feet / hour less than twice the first rate
X = 2x - 10 eq3
take eq1 and eq 2
( total time = t 1 + t 2 = T)
T = 1000/x + 5000/X
but X = 2x-10
T = 1000/x + 5000/( 2x -10)
T = 1000/x + 5000/( 2(x-5))
T = 1000/x + 2500 / (x-5)
Answer / Explanation
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Question:
The stem and leaf plot shows kilometers walked by participants in a charity benefit walk. Use it to answer the question
12|3 3 6 7 9 9
13| 1 1 4 5 5
14| 0 0 2 3 3 8 8 9
15| 2 2 2 2 2 3 5 5 7
16| 4 5 5 9 9
17|3 5
(a) How many people participated in the walk? Exactly 35 people participated in the walk.
(b)How many of the walkers traveled more than 14 kilometers? About 16-22 people traveled more than 14 kilometers.
Answers:
(a) Exactly 35 people participated in the walk.
(b) About 16-22 people traveled more than 14 kilometers.