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i am going with 1/16 as hugo is the pilot and with 9/16 as exactly 1 copilot has less than 500 hours.
total 4 pilots, copilots 6 in total
case 1: hugo is the pilot- the 2 copilots must both be exp, choose 2 out of 3 = 3 ways
case 2: hugo is not the pilot - 2 copilots out of 6 available = 15 ways
total scenario = 3x15 = 45, total valid crew = 3+45 = 48 ways
prob hugo is pilot = 3/48 = 1/16
prob exactly 1 copilot has less than 500 hours - 27/48 = 9/16
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Ways for ONLY Hugo = 1 x 3C2 (copilots with 500+ hours) = 1 x 3 = 3
Ways for others = 3C1 x 6C2 = 3 x 15 = 45
Total = 45 + 3 = 48

P(Hugo) = 3/48 = 1/16

Ways for ONLY 1 copilot with 500+ = 3C1 (copilots 500+) x 3C1 (copilots less than 500) x 3C1 (Pilots) = 27

P(ONLY 1 Copilot with 500+) = 27/48 = 9/16
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Answer: Hugo is the pilot = 1/16, Exactly 1 co-pilot less than 500 hrs = 9/16

Hugo is the pilot:
Total number of desirable outcomes = all outcomes where there are two co-pilots with >500 hrs = 1C1 * 3C2 = 3
Total number of possible outcomes = 4C1 * 6C2 - Invalid crews (hugo is pilot but co-pilots don't both have >500 hrs) = 60 - 12 = 48
3/48 = 1/16

Exactly 1 co-pilot less than 500 hrs:
Total number of desirable outcomes = 3 possible pilots * 3 possible experienced co-pilots * 3 possible less experienced co-pilots = 27
Total number of possible outcomes = 48
27/48 = 9/16
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total possible crews =

When Hugo is pilot = 1c1 * 3c2 = 3

When Hugo is not pilot = 3c1* 6c2 = 45

Total = 48

Now P that hugo is pilot = 1c1*3c2 / 48 = 3/48 = 1/16

When 1 copilot is experienced one isnt = (hugo cant be pilot now) = 3c1*3c1*3c1 / 48 = 27/48 = 9/16
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Let copilot be
3 e [>500]
3 l [<500]

Total Valid crews:
Hugo as pilot: choose 3 e = c(3,2) = 3
other 3 pilots: can fly with any 2 of 6 copilots = 3 * c(6,2)
= 3*15 = 45
total valid crews = 3+45 = 48

1. Prob Hugo is pilot:
= 3/48
= 1/16

2. Prob exactly 1 copilot l[<500]
choose 1 exp and 1 less exp copilot
c(3,1) * c(3,1) = 3*3 = 9
only the other 3 pilots can fly with this combinations
3*9 = 27
Prob = 27/48 = 9/16
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P(Hugo)=1/4
p(Copilot>=500)=3/6 =1/2 p(copilot<500)=1/2
Hugo cant fly without both copilots>=500 hrs of flying experience
P(1 copilot <500 and 1 copilot>=500)=3/4*1/2*1/2=3/16
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The cockpit crew for a long-haul flight must consist of 1 pilot and 2 copilots, selected from an available pool of 4 pilots and 6 copilots. One of the pilots, Hugo, is only certified to serve as pilot if each of the two selected copilots has at least 500 hours of flight experience, a qualification held by 3 of the 6 available copilots. The remaining pilots can fly with any copilot. A cockpit crew will be selected at random from all possible crew combinations that meet these conditions.


Hugo can be pilot if 2 co pilot have > 500 hours flight experience , which 3 out 6 have
3c2 , 3 ways to select that co pilot
total combination to select co pilot
6c2 = 15 ways
there are 3 other pilots we have total of
15*3 45 ways

total combination will be 45+3 ; 48


hugo is pilot P will be = 3 /48 ;

1/16 is correct

for second case s probability that exactly 1 of the 2 copilots < 500 hours

total ways will be

total 3 pilots * 3c1 ( pilots with experience ) * 3c1 ( pilots who have no experience)

3c1 * 3c1 * 3c1 = 27 ways

27/48 ; 9/16

1/16 & 9/16 are correct options
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Cockpit crew : 1 pilot + 2 copilots
Availability : 4 pilots & 6 copilots

Hugo (pilot) - > Each of 2 copilots has > 500 hours of flight experience ( 3 out of 6 copilots have this qualification)
Remaining 3 pilots - > Any 2 copilots out of 6.

Total selections possible = 1*3C2 + 3C1*6C2 = 1*3 + 3*15 = 48

The number of selections with Hugo as pilot = 1*3C2 = 3

The probability that Hugo is a pilot on the selected crew = 3/48 = 1/16

The number of selections with exactly 1 copilot has < 500 hours experience = 3C1 * 3C1 * 3C1 = 27

The probability that exactly 1 copilot has < 500 hours experience = 27/48 = 9/16

Hugo is the pilotExactly 1 pilot has less than 500 hours
1/169/16
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The cockpit crew for a long-haul flight must consist of 1 pilot and 2 copilots, selected from an available pool of 4 pilots and 6 copilots. One of the pilots, Hugo, is only certified to serve as pilot if each of the two selected copilots has at least 500 hours of flight experience, a qualification held by 3 of the 6 available copilots. The remaining pilots can fly with any copilot. A cockpit crew will be selected at random from all possible crew combinations that meet these conditions.

Total value crews with Hugo as Pilot= 1*3C2 = 3
Total valid crews with other 3 pilots = 3*6C2= 45
Total valid cases= 3+45= 48

1. When Hugo is the Pilot = 3/48= 1/16

2. Exactly 1 copilot has less than 500 hours.
Needed Copilot pairs= 3C1*3C1 =9
Except Hugo other 3 pilots can be chosen = 3
Crew can be selected=9*3= 27
Required probability= 27/48= 9/16
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Our first step in this question would be to make total number of ways of choosing different crew.
For total ways of different crew:
Case 1; when Hugo is the pilot, we would have only 3 copilots to choose(as given)
1 way to choose Hugo and 3C2 ways to choose copilot
1 * 3 = 3 ways

Case 2: when Hugo is not the pilot:
3C1 ways to choose pilot and 6C2 (=15) ways to choose copilot
3 * 15 = 45 ways

Total ways to choose different crews = 3 + 45 = 48 ways

(I) Now P(Hugo is the pilot) = 3/48 = 1/16
(II) P(Exactly 1 copilot has less than 500 hours) - Hugo's case would be eliminated as he requires both copilots to have at least 500 hours of flight experience.

Ways to make different crews with 1 copilot with less than 500 hours of flight experience:
Choose pilot(3C1), Choose one copilot of the 3 with at least 500 hours of flight experience(3C1) and choose one copilot with less than 500 hours of flight experience(3C1)
= 3 * 3 * 3 = 27 = total ways to make different crews with less than 500 hours of flight experience
P(Exactly 1 copilot has less than 500 hours of flight experience) = 27/48 = 9/16

(I) 1/16
(II) 9/16
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4 pilots (including Hugo)
6 copilots ( 3 with over 500 hours, 3 less than 500)

Hugo can only fly with two experienced copilots
Number of crews is 3 choose 2 equals 3

Other pilots can have any copilots pair. 6 choose 2 equals 15

therefore three pilots can have 3 x 15 = 45 possibilities

Therefor total number of valid crews is

3 + 45 = 48

If Hugo is pilot than probability is
3/48 or 1/16

Exactly one copilot has less than 500 hours
1 less than 500 hours from 3
1 more than 500 hours from 3

number of pairs is 3x3=9
these pairs can not fly with Hugo

number of valid crews with exactly one pilots with under 500 hours is

9 x 3 = 27

27/48 = 9/16
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Hugo as a Pilot - condition - both Copilot > 500 exp
Not Hugo as a Pilot - condition - anyone can be a copilot.
So, case 1 - Hugo as a Pilot - the other 2 can be 3c2 = 1(Hugo)*3 (out of 3 exp we can select 2)
case 2 - Not Hugo as a Pilot - space can be filled as - 3c1(pilots) * 6c2(other two copilots) = 45
Total. combination - 45 + 3 = 48
1. Now, Hugo Pilot - prob - 3/48 = 1/16
2. exactly one copilot with less than 500 exp
In this hugo can't be the pilot(since he needs both copilot > 500 exp)
So, the remaining pilot can be 3, and for the copilot, we need to pick exactly 1 with less than 500 exp - so ->
combination - 3(no of remaining pilot) * 3c1(one with > 500 exp) * 3c1(one with < 500 exp) = 27
prob - 27/48 = 9/16

So, answer = 1/16, 9/16
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I have taken a slightly rudimentary approach as I have not finished studying this topic.
Happy to see the best method. here is how I did it:

We have four pilots, Hugo + 3 others.
Let's call them A, B, C, H (Hugo)

We have 6 co-pilots, let's call them:
1,2,3,4,5,6
Out of these, only three have 500+ hours of flying experience (Let them be 1,2,3)

Since we need to find the probabilbity of Hugo being the pilot, let's look at all possible combinations.
First for 'A':
A (paired with) 12 | 13 | 14 | 15 | 16 |
A (paired with) 23 | 24 | 25 | 26 |
A (paired with) 34 | 35 | 36 |
A (paired with) 45 | 46
A (paired with) 56
Total possibilites for A- 15.

Similarly, since B & C can also fly with any copilot, pairings for them also will be 15 each.

For H-
H (paired with) 12 | 13 |
H (paired with) 23 |
Total possibilites for H- 3

Total possibilities across pilots- 15+15+15+3= 48

Therefore probability of Hugo being the pilot- (3/48) = (1/16)
---
Now, let's look at the probability of Exactly one copilot with LESS than 500 hours.
Or in other words, with only one copilot with MORE THAN 500 hours.

If you see the table above, for A its possible only in 9 cases (14 | 15 | 16 | 24 | 25 | 26 | 34 | 35 | 36)
(Since we had assumed that 1,2 & 3 have over 500 hours of flying experience.

Similary for B & C as well there will be 9 cases each.
For Hugo, there will be no cases as BOTH copilots need to have over 500 hours of flying experience.

Hence, we get: (9+9+9)/48
=27/48
=9/16

Therefore the answers are:
| 1/16 | 9/16 |
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total valid combination = when the other 3 pilots are selected + when Hugo is selected = 3c1*6c2 + 3c2 = 45 + 3 = 48
Case 1: Hugo is the pilot:
2 out of 3 valide copilots can be onboarded. so 3c2 = 3
total = 48
so, P(1) = 3/48 = 1/16
Case 2: exactly 1 copilot with less that required exp.
We can ignore Hugo case as both should be more expd.
and we have 3 with less exp and 3 with more experience, so that combination will be
3c1(selecting one pilot out of 3) * 3c1(selecting 1 copilot with less exp)*3c1(selecting 1 copilot with more exp) = 27
so P(2) = 27/48 = 9/16
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IMO : 1/16 for the 1st one and 9/16 for the 2nd one
although not so sure
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Pilotcopilotcombination possible
typ1 t<500hr133
typ2363*6C2=3*15=45
total48

Hugo is type 1 = P(H) =3/48=1/16

Prob of 1 of 2 copilots having t<500hrs means Hugo can be selected so combo possible is =3C1*3c1*3C1=27
P=27/48=9/16
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Hugo is the only certified to serve as pilot if each of the two selected co pilots has at least 500 hours of flight experience.
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