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# Maths Exam Style Question HELP!!!

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1. So Anyone know how to solve it WITHOUT GIVING ME THE ANSWER with a step by step guide which would help me figure it out!
2. What have you tried so far?
3. (Original post by Donkey******)
What have you tried so far?
I have tried 300/400 = 3/4*2 (as they are rolling the die twice) but i dont think that is the right answer!
4. yeah sounds about right to me, you have worked out the probability of getting heads and getting heads twice in a row is 3/4^2 (or 3/4 to the power of 2)
5. (Original post by NothingButWaleed)
I have tried 300/400 = 3/4*2 (as they are rolling the die twice) but i dont think that is the right answer!
Because it's not. Get the probability that it will land on heads and square it to get the probability for it happening twice. You have to square it because you're multiplying the two probabilities together in order to find the probability of it happening twice in total.

By your logic, if I throw a coin twice with an equal chance of both tails and heads, the probability of me getting two heads is which is obviously not right.
6. (Original post by metaljoe)
yeah sounds about right to me, you have worked out the probability of getting heads and getting heads twice in a row is 3/4*2.
Probability doesn't go above 1, it is bounded between 0 (impossible for something to happen) and 1 (full certainty of it happening), and
7. (Original post by NothingButWaleed)

So Anyone know how to solve it WITHOUT GIVING ME THE ANSWER with a step by step guide which would help me figure it out!
First, you need to work out the total times it was flipped, and how many heads or tails.

Then, you want to work out the probability oh heads being the outcome.

Finally, since you are flipping the coin twice, you square the probability of it landing on heads.

Spoiler:
Show
So, 400 times total, 300 heads, 100 tails.

The chance of landing on heads is 3/4

So you do 0.75 * 0.75 which is 0.5625, which is your answer

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