So I was watching Avengers Infinity War and heard of Thanos’s plan to kill half of the universe. That got me to thinking about probability and I was inspired to write out some questions for my students. Questions and answers are below. Have fun!

Questions

Answers

---

1) Loki has a 90% chance of resurrecting every time he dies in a movie. Given that Loki has already “died” twice in previous movies, what is the probability he will resurrect from dying in Infinity War?

Answer: 0.9 All death events are independent
Real answer: Depends on how many fan girls want him back

---

2) The Avengers must work together successfully to have the only chance to defeat Thanos. Given that Starlord has a 10% chance of not letting his emotions get the better of him, Spiderman has a 40% chance of not acting like a teenager and obeying Stark’s orders, Hulk has a 50% chance of not sulking and being able to transform when needed. What is the chance of Thanos being defeated?

Answer: Probability Thanos is defeated = 0.1 x 0.4 x 0.5 = 0.02
Real answer: We are all going to die or rather half of us are going to die

---

3) Given that the power scale of a character is inversely proportional to the chance of dying while fighting against Thanos. Thor has a power scale of 10000 and has a 20% chance of dying. Iron man has a power scale of 8000 and Black Panther has a power scale of 1000. Is iron man or black panther more likely to die in a face off against Thanos?

Answer: Black Panther
Let p represent power scale and d represent chance of dying
p α 1/d   => p k/d => Sub (10000, 0.2) into the equation => 10000 = k/0.2 => k = 2000
for iron man p = 2000/d => sub 8000 => 8000 = 2000/d => d = 0.25 = 25% chance of dying
for black panther p = 2000/d => sub 1000 => 1000 = 2000/d=> d = 0.50 => 50% chance of dying
Real answer: Iron man. Disney will never let Black Panther die when it brought in a box office revenue of $1.3 billion worldwide $$$

---

4) Given that there are 5 people in your family including you, if Thanos snaps his finger with the infinity gauntlet to kill half of the universe randomly, what is the probability all 5 members of your family survive?

Answer: Thanos wants to kill half of the universe. So for every 2 people, 1 person will die.
So chance of dying is 0.5
Probability all 5 members in the family do not die = (0.5)⁵ = 0.03125
Real answer: It doesn’t matter. Knowing the odds will not change the outcome in any way.

---

5) Given that Gamora gives Thanos 10 possible locations for the soul stone to try to slow him down.

1. What is the probability that Thanos will find it on his 5th try?
2. What is the probability Thanos will not find the stone in the first three tries?

Answer:

1. Probability =9/10 x 8/9 x 7/8 x 6/7 x 1/6 = 0.1
2. Probability = 1 – (1/10 + 9/10 x 1/9 + 9/10 x 8/9 x 1/8) = 0.7

Real answer: Space stone will allow user to be in multiple locations at once (especially since Thanos has the power stone to power the space stone. Nice try, Gamora)

---

6) Thanos kept his six infinity stones in his right pocket during his retirement. He also put 5 of his chocolates bars in the same pocket in case he gets hungry. What is the probability that he will pick out 2 chocolate bars in a row without looking?

Answer: Probability = 5/11 x 4/10 = 2/11
This question is without replacement.
Real Answer = 1. he can easily feel if object is spherical or cuboid, genius!

---

7) Thanos love the number 6 so he decides to use the reality stone to alter all dice rolls in the universe to show the number 6 with a probability of 40% and the other numbers equally likely to appear. What is the probability of 6 appearing at least once in 2 dice rolls now?

Answer:
Method 1: (probability both are 6) 0.4 x 0.4 + (probability 1^st dice is 6, 2^nd dice is not) 0.4 x 0.6 + (probability 1^st dice is not 6, 2^nd dice is 6) 0.6 x 0.4 = 0.64

Method 2: 1 – (probability that six does not show up in both throws) 0.6 x 0.6 = 0.64
Real Answer: All maths teachers are going to have to change their answers in the mark scheme now

---

8) You want to go watch Avenger Infinity War with a friend. Given that you have 10 male friends and 10 female friends and 80% of males like and will watch the show and 50% of females like and will watch the show. what is the probability the friend you go with is a girl?

Answer: There are only 8 guys and 5 girls that want to watch.
Probability of picking a girl will be (number of girls/ divide total number of people) = 5/13
Real answer: Just ask the one you want to go with 😊

---

9) Bonus Question for Lower Sec Science: Given that when Thanos snaps his fingers to kill half the universe in a random order and Gamora who he loves as daughter dies as a result, what scientific attitude is he displaying?

1. Curiosity
2. Perseverance
3. Open mindedness
4. Integrity

Answer: Integrity
Real answer: He is not fit to be a father