How to you calculate the age of a ancestor from limited information. What do I have available to calculate the age? Census records for 1841, 8151 and 1861, death certificate, Bishop Transcripts, Parish Records. Using the census records I have the following information:

Option #1
* 1841 – 50 years old. Math calculation: 1841 – 50 =  1791
* 1851 – 62 years old. Math Calculation 1851 – 62 =  1789
* 1861 – 72 years old. Math Calculation 1861 – 72 =  1789

Taking the median of my math calculations: [1789, 1789, 1791]. He may have been born in 1789. This calculation is based on my genealogy course work using the median for calculating the age. I have considered the other two options before making a decision.

Option#2
Death Certificate – reports age to be 77 years old. Died in 1864. Math calculation: 1864 – 77 = 1787.
Parish records and Bishop Transcripts show age of death to be 77 years old.

Option #3
Date of Birth Calculator located at http://www.f-tree.org.uk/index.php . The birth calculator is used for English genealogy. Using the birth calculator from the above stated census, death certificate and parish records the calculator shows the birth to be between 31 March 1786 and 06 June 1791. This calculation fits the Option 1 & Option2.

The above stated options provides the birth year to be between 1786-1791. I chose option #2 for stating the birth year and will consult other sources.