A total of 50 students play either soccer or lacrosse.

• 20 girls play lacrosse
• 20 boys play either soccer or lacrosse
• 20 students play soccer

What is the probability that a student plays soccer or is a girl.

The two-way table shows the number of births, in thousands, in the United States for the years 2010 and 2011.

A baby born in 2011 is randomly selected.
What is the probability that the baby was born in February?

Jeremy wants to know the density of a rock in grams per cubic centimeter.  The rock has a mass of 1.08 kilograms and a 
volume of 400 cubic centimeters.  What is the density of the rock in grams per cubic centimeter?  (g/cm³)

Line k has a slope of -5.  Line j is perpendicular to line k, and passes through the point (5,9).  Create the equation for line j.

A right triangle is shown.  What is cos A?

Create the equation of a line that is perpendicular to 2y = 14 + (2/3)x and passes through the point (-2,8).
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In this figure, triangle GHJ is similar to triangle PQR.

Based on this information, which ratio represents tanH ?
A.)  8/15
B.)  8/17
C.)  15/8
D.)  17/8

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The figure shows ∆ABC ∼ ∆DEF with side lengths as indicated.

What is the value of x?
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Triangle XYZ is shown.

Which triangle must be similar to triangle XYZ ?
​A.)  a triangle with two angles that measure 40°
B.)  a triangle with angles that measure 40° and 60°
C.)  a scalene triangle with only one angle that measures 100°
D.)  an isosceles triangle with only one angle that measures 40°
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A study reports that in 2010 the population of the United States was 308,745,538 people and the land area 
was 3,531,905 square miles.  

Based on the study, what was the population density, in people per square mile, of the United States in 2010? 
Round your answer to the nearest tenth.