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Yes, there will be a point in time when the distance between any two pairs of cars will again be x miles.
Let’s assume that the track has a circumference of C miles. When the leading car catches up with the last car, it will have completed one full lap of the track, and the other two cars will have completed some fraction of a lap. Let’s call this fraction f, where 0 < f < 1.
At this point, the leading car is at the starting point, and the other two cars are x miles apart on the track. The middle car is fC miles ahead of the trailing car, and (1-f)C miles behind the leading car. The trailing car is x + fC miles behind the leading car, and (1-f)C – x miles ahead of the middle car.
As the cars continue to move, the distance between the leading and middle car will decrease at a rate of 55 – v miles per hour, where v is the speed of the middle car. Similarly, the distance between the middle and trailing car will increase at a rate of v – 45 miles per hour.
There will be a point in time when the distance between the leading and middle car, and the distance between the middle and trailing car, are both equal to x. Let’s call this time t. At time t, the distance between the leading car and the middle car will be x, which means that the middle car will be (1-f)x miles behind the leading car. The distance between the middle car and the trailing car will also be x, which means that the trailing car will be x + fC – (1-f)x = fC + x miles behind the leading car.
We can solve for t by setting the distances equal to x and solving for v. We get:
55t – vx = 55x vx – 45t = 45x
Solving for v and equating the two expressions, we get:
v = (55x + 45t) / (t + x)
Substituting this expression for v into the equation for the distance between the middle and trailing car, we get:
fC + x = vt – 45t = (55x + 45t) / (t + x) * t – 45t
Solving for t, we get:
t = C / (10 + 2f)
This is the time at which the distance between any two pairs of cars will again be x miles. Note that this time will be different for different values of f, but there will always be a time when the distance between the cars is x.
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Let’s assume that the three dresses are indistinguishable and that each girl picks a dress at random. There are 3! = 6 ways that the girls can pick the dresses, since each girl can pick from any of the three dresses, and there are 3 ways to assign the first girl’s choice, 2 ways to assign the second girl’s choice (since one dress is already chosen), and 1 way to assign the third girl’s choice (since two dresses are already chosen).
Out of these 6 possible ways, we need to count the number of ways that no girl picks her own dress. We can use the principle of inclusion-exclusion to do this.
Let A, B, and C denote the events that the first, second, and third girl, respectively, picks her own dress. Then, we want to calculate the probability of the event not(A or B or C), which is the complement of the event A or B or C. By the principle of inclusion-exclusion, we have:
P(not(A or B or C)) = 1 – P(A or B or C) = 1 – (P(A) + P(B) + P(C) – P(A and B) – P(A and C) – P(B and C) + P(A and B and C))
Since each girl picks a dress at random, we have:
P(A) = 1/3 P(B) = 1/2 (since one dress is already chosen, the second girl has only 2 choices) P(C) = 1 (since there is only one dress left for the third girl)
Also, we have:
P(A and B) = 1/3 * 1/2 = 1/6 P(A and C) = 1/3 * 1/1 = 1/3 P(B and C) = 1/2 * 1/1 = 1/2
Finally, we have:
P(A and B and C) = 1/3 * 1/2 * 1/1 = 1/6
Substituting these values into the formula above, we get:
P(not(A or B or C)) = 1 – (1/3 + 1/2 + 1 – 1/6 – 1/3 – 1/2 + 1/6) = 1/3
Therefore, the probability that no girl will choose her own dress is 1/3.
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To guarantee at least one “four of a kind,” we need to find the worst-case scenario in which we keep taking cards out without getting a four of a kind. In other words, we want to keep removing the cards that are least likely to help us get a four of a kind.
There are 13 ranks in a standard deck of cards (Ace, 2, 3, 4, 5, 6, 7, 8, 9, 10, Jack, Queen, King), so there are 13 possible four of a kinds. In order to guarantee getting at least one four of a kind, we need to have at least 13 * 4 = 52 cards in our hand (since we need one card of each rank to make a four of a kind).
However, the question asks for the minimum number of cards that must be taken out from the mixed cards to guarantee a four of a kind. So we need to think about the worst-case scenario, where we keep taking out cards without getting a four of a kind.
The worst-case scenario occurs when we take out 48 cards without getting a four of a kind. At this point, we have 4 cards from each rank in our hand, and the next card we draw will complete at least one four of a kind. So the minimum number of cards that must be taken out to guarantee at least one four of a kind is 48.
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Let’s consider the scenario where the second child in H1 is a girl. In this case, we know that H1 has two children: one boy who plays for the Mexico Youth academy and one girl who plays baseball. The probability of H1 having a girl child is 1/2, because one of the two children is a girl.
For H2, we know that they have two children: one boy who plays soccer for his school and a newborn, whose gender we do not know. there are two possible cases:
- Case 1: H2’s newborn is a boy. In this case, H2 has two boys and no girl.
- Case 2: H2’s newborn is a girl. In this case, H2 has one boy and one girl.
Assuming that the probability of having a boy or girl is the same, the probability of Case 1 is 1/2, and the probability of Case 2 is also 1/2. Therefore, we can compute the overall probability of having a girl child in H2 as before:
P(girl in H2) = P(girl in Case 1) * P(Case 1) + P(girl in Case 2) * P(Case 2) = 0 * 1/2 + (1/2) * 1/2 = 1/4
So the probability of having a girl child in H2 is 1/4.
Since the probability of having a girl child in H1 is now 1/2 and the probability of having a girl child in H2 is 1/4, we can conclude that the probability of House H1 having a girl child is actually higher than that of House H2 in this scenario.
But if the 2nd child on house H1 is a boy then the answer is opposite.- 1085 views
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Answer: 14 minutes
If I cut the 50 feet long of cloth into 10 pieces of 5 feet long it takes 10 minutes. Than I stack the pieces of cloth on top of each other and cut them all at the same time, making 4 more cuts to split each piece into 5 one-foot-long handkerchiefs so another 4 minutes
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Here are some:
- Finland and Andorra > finlandorra
- Serbia and Biafra > Serbiafra
- Ireland and Andora > Irelandora
- Belarus and Russia > Belarussia
- Sweden and Denmark > Swedenmark
- Vietnam and Namibia > Vietnamibia
- Nauru and Uruguay > Nauruguay
- Nicaragua and Guatemala > Nicaraguatemala
- Niger and Germany > Nigermany
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I will put one blue gem in one sack and the other 99 gems into the sack with the red gems so now the probability will we 0.5 * (1/1 + 99/199) = 0.7487 which is almost 3/4
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Anwer: 2 Hours
Explanation:
Jacob can eat 2 chocolates in 10 minutes so in one hour he can eat 60 * 2 / 10 = 12
Jolly can eat 7 chocolates in 20 minutes o in one hour she can eat 60* 7 /20 =21
So in one hour they can eat 27+12+21 =60
so it takes 2 hours to eat 120 chocolates.- 953 views
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The problem is because of vapor barrier. The chocolate ice cream is probably located at the entrance to the store and because its more popular , in a separate container ant the time to buy it is short, However the strawberry ice cream is located at the back of the store probably with a small queue, so shopping time is longer. So when it takes more time to buy the ice cream, the engine was enough to cool down, and the vapor plug would open, while when buying the chocolate ice cream the steam is not released to the engine chokes.
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If a material floats on another then obviously the first material is lighter. So the answer is: False
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