# TSI Math: How Many Times Will Jaqen Roll Two 10s?

Jaqen has two 10-sided dice. He rolls both at the same time. What is the probability that both faces add up to a number less than 20?

Data Analysis, Statistics, and Probability | Probabilistic Reasoning |

Mathematics and Statistics Assessment | Probabilistic Reasoning |

Product Type | TSI |

TSI | Mathematics and Statistics Assessment TSI Math TSI Mathematics |

TSI Math | Data Analysis, Statistics, and Probability |

TSI Mathematics | Data Analysis, Statistics, and Probability |

Test Prep | TSI |

### Transcript

combination of faces adds up to a number less than

twenty much faster to find the probability of rolling two

tens and find the probability of all the other possible

roles so just take the shortcut there Well the probability

of rolling ten on one dies one in ten because

each of the ten faces has an equal probability of

turning up The probability of rolling to tens then is

one over ten times one over ten or one over

one hundred or one percent The probability of rolling anything

other than two tens and a rowing to faces that

add up to a number less than twenty is one

minus the probability of that one hundred shot So it's

ninety nine out of one hundred probability that both faces

add up to a number less than twenty is ninety

nine out of one hundred And yeah we like those

odds So the answer is c and we're so shmoop