Astronomy 23/223 In-Class Exercise:

Solution: How Old is our Solar System?

 

X Data

Xi



Xi2		 Y Data

Yi



Yi 2

Xi·Yi
Sample 1 0.03298 0.001088 0.70127 0.491780 0.023128
Sample 2 0.04614 0.002129 0.70209 0.492930 0.032394
Sample 3 0.02414 0.000583 0.70060 0.490840 0.016912
Sample 4 0.17130 0.029344 0.70954 0.503447 0.121544
Sample 5 0.15250 0.023256 0.70840 0.501831 0.108031
Sample 6 0.13800 0.019044 0.70748 0.500528 0.097632
Sample 7 0.13650 0.018632 0.70758 0.500669 0.096585
Sample 8 0.12680 0.016078 0.70733 0.500316 0.089689
Sample 9 0.09050 0.008190 0.70497 0.496983 0.063800
Sample 10 0.07280 0.005300 0.70373 0.495236 0.051232
SUM 0.99166 0.123644 7.05299 4.97456 0.700948

= 0.99166 = 7.05299
   
= average X = 0.099166 = average Y = 0.705299
   
= 0.123644 = 4.97456
   
= 0.700948  
   

Now, solve either form of the following two equations, and you’ll know the equations of your line!

 

slope = 0.060497

 

 
 
intercept = 0.6993
Equation for regression line is: Y = slope · X + intercept
Y = 0.060497 X + 0.6993
Age = ln(slope+1)/1.42x10-11
Age = 4.136x109 years

 


Home | Syllabus | Course Schedule | Images and Data | Homework | Homework Answers
In-Class Exercises | In-Class Answers | Exam Review | Exam Answers | Student List | Contact Darby
| Summer Internships | More on Astronomy| Bus Schedule

This page was created by Darby Dyar and is maintained by Darby Dyar and Rebekah Robson-May.
Last updated on 19 April, 2002.