Years Since 1970, x: 0, 10, 20, 30, 40
Population (In thousands), y: 489, 801, 1,202, 1,998, 2,959
Find the population for 1975.
A. 623 thousand people.
B. 599 thousand people
C. 513 thousand people
D. 650 thousand people
To find the population for 1975, we can interpolate using the given data points for 1970 and 1980.
Using the formula for linear interpolation:
Population for 1975 = Population for 1970 + [(Population for 1980 - Population for 1970) * ((number of years since 1970) / 10)]
Population for 1975 = 489 + [(801 - 489) * ((5) / 10)]
Population for 1975 = 489 + [(312) * (0.5)]
Population for 1975 = 489 + 156
Population for 1975 = 645 thousand people
Therefore, the closest option is D. 650 thousand people.