Aptitude Discussion

Q. |
If the probability that $X$ will live 15 year is 7/8 and that $Y$ will live 15 years is 9/10, then what is the probability that both will live after 15 years? |

✖ A. |
1/20 |

✔ B. |
63/80 |

✖ C. |
1/5 |

✖ D. |
None of these |

**Solution:**

Option(**B**) is correct

Required probability

\(=\dfrac{7}{8}\times \dfrac{9}{10}\)

\(=\dfrac{63}{80}\)

**Suman**

*()
*

**Ravi**

*()
*

The answer must be none of these.

The question asks the probability of both living after 15 years,

but the data given is probability of living upto 15 years

I AGREE with ravi ,the sample space is undefined ,therefore HOW can we decide the probability after 15 years