# May 2019

**Problem**

Solve for *x* from the following equations:

$xy = 12$ | $yz = 20$ | $zx = 15$ |

A. 2 | C. 4 |

B. 3 | D. 5 |

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- 46 reads

**Problem**

A germ population has a growth curve $Ae^{0.4t}$. At what value of $t$ does its original value doubled?

A. t = 7.13 |
C. t = 1.73 |

B. t = 1.37 |
D. t = 3.71 |

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**Problem**

A circle has an equation of $x^2 + y^2 + 2cy = 0$. Find the value of $c$ when the length of the tangent from (5, 4) to the circle is equal to one.

A. 5 | C. 3 |

B. -3 | D. -5 |

**Problem**

Find the equation of the curve passing through the point (3, 2) and having s slope 5*x*^{2} - *x* + 1 at every point (*x*, *y*).

A. $y = \frac{5}{3}x^3 - \frac{1}{2}x^2 + x - \frac{31}{3}$ | C. $y = 5x^3 - 2x^2 + x - 118$ |

B. $y = 5x^3 - 2x^2 + x - 31$ | D. $y = \frac{5}{3}x^3 - \frac{1}{2}x^2 + x - \frac{83}{2}$ |

**Problem**

The number of hours daylight, *D*(*t*) at a particular time of the year can be approximated by

for *t* days and *t* = 0 corresponding to January 1. The constant *K* determines the total variation in day length and depends on the latitude of the locale. When is the day length the longest, assuming that it is NOT a leap year?

A. December 20 | C. June 20 |

B. June 19 | D. December 19 |

- Read more about Longest Day of the Year: Summer Solstice
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- 323 reads

**Problem**

The local weather forecaster says “no rain” and his record is 2/3 accuracy of prediction. But the Federal Meteorological Service predicts rain and their record is 3/4. With no other data available, what is the chance of rain?

A. 3/5 | C. 1/6 |

B. 1/4 | D. 5/12 |

- Read more about What is the Chance of Rain: Local vs Federal Forecasts
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