A high school had 1200 students enrolled in 2003 and 1500 students in 2006. If the student population P ; grows as a linear function of time t, where t is the number of years after 2003.
a) How many students will be enrolled in the school in 2010? Choose the correct choice from the following:
A) 1800 B) 1900 C) 1700 D) 1500 E) 1600
a) The given information may be written as ordered pairs (t , P). The year 2003 correspond to t = 0 and the year 2006 corresponds to t = 3, hence the 2 ordered pairs   (0, 1200) and (3, 1500)   Since the population grows linearly with the time t, we use the two ordered pairs to find the slope m of the graph of P as follows   m = (1500 - 1200) / (6 - 3)= 
<gadget id="calculator">(1500 - 1200) / (6 - 3)</gadget>
<output>100</output>
100 students / year   The slope m= 100 means that the students population grows by 100 students every year. From 2003 to 2010 there are 7 years and the students population in 2010 will be   P(2010) = P(2003) + 7 * 100 = 1200 + 700= 
<gadget id="calculator">1200 + 700</gadget>
<output>1_900</output>
1900 students   Answer 1900
<result>B</result>
A high school had 1200 students enrolled in 2003 and 1500 students in 2006. If the student population P ; grows as a linear function of time t, where t is the number of years after 2003.
a) How many students will be enrolled in the school in 2010?