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What is the probability of rolling a total of $7$ with two dice at least once in $10$ rolls?

Answer
VerifiedVerified
507.9k+ views
Hint: Probability is a branch of mathematics concerned with empirical representations of the likelihood of an occurrence occurring or the truth of a proposition. The probability of an event is a number between $0$ and $1$, with $0$ indicating impossibility and $1$ indicating certainty.

Complete step-by-step solution:
A six-sided cube with the numbers $1 - 6$ on the faces is the most common type of die.
When we roll a die there are $6$possible outcomes. Hence, there are $36$ possible outcomes when flipping two dice.
Six of the $36$ outcomes have a total of seven:
$\left\{ {1\, + \,6,\,2\, + \,5,\,3\, + \,4,\,4\, + \,3,\,5\, + \,2,\,6\, + \,1} \right\}$
That is, $30$ of the $36$ possible outcomes will not be a total of $7$.
$\dfrac{{30}}{{36}}\, = \,\dfrac{5}{6}$
$\dfrac{5}{6}$ of the time, we will not get a total of $7$ on the first roll.
i.e., We didn't get a $7$ on the first roll $\dfrac{5}{6}$ of the time.
$\dfrac{5}{6}$ of the time, we will not get $7$ on the second roll.
That is, we will not get a total of $7$ on either of the first two rolls $\dfrac{5}{6}\, \times \,\dfrac{5}{6}\, = \,{\left( {\dfrac{5}{6}} \right)^2}$ of the time.
Following this logic, we can see that ${\left( {\dfrac{5}{6}} \right)^{10}}$ of the time, we will not get a total of $7$ on any of the first $10$rolls.
i.e.; Approximately $16.5\,\% $ of the time, we will not get a total of $7$on any of the first $10$ rolls.
This means that at least one of the first ten rolls would result in a total of $7$.
$100\,\% \,\, - \,16.5\,\% \, = \,83.85\,\% \,$
Hence, the probability of rolling a total of $7$ with two dice at least once in $10$ rolls is $83.85\% $

Note: The higher an event's probability, the more likely it is that it will occur. The underlying dynamics and regularities of complex systems are often defined using probability theory.