Combining Groups of Percentages

[mrtheduke]

Hi,
I have a set which shows the percentage of different ages, nationally, that use a smartphone:

	16- 24	25- 34	35- 44	45- 54	55- 64	65+
Smartphone	87%​	91%​	93%​	92%​	85%​	59%​

and another set which shows the number of people in different age groups within a specifc geographical area:

Age 16-24	711​
Age 25-64	4496​
Age 65+	2870​

I need to use the first set to forecast the likely number of smartphone users in each of the groups in the second set. The 16-24 and 65+ age groups are obviously straightforward, but for the other age groups, the data in the second set is less granular. To get the percentage of people aged 25 - 64 who use a smartphone, is it simply a case of adding the 25-34, 35-44, 45-54 and 55-64 percentages together and divide them by 4? Thanks

 

[Dr.Peterson]

Hi,
I have a set which shows the percentage of different ages, nationally, that use a smartphone:

	16- 24	25- 34	35- 44	45- 54	55- 64	65+
Smartphone	87%​	91%​	93%​	92%​	85%​	59%​

and another set which shows the number of people in different age groups within a specific geographical area:

Age 16-24	711​
Age 25-64	4496​
Age 65+	2870​

I need to use the first set to forecast the likely number of smartphone users in each of the groups in the second set. The 16-24 and 65+ age groups are obviously straightforward, but for the other age groups, the data in the second set is less granular. To get the percentage of people aged 25 - 64 who use a smartphone, is it simply a case of adding the 25-34, 35-44, 45-54 and 55-64 percentages together and divide them by 4? Thanks

Clearly, since the data do not match up, the best you can do is to attempt some approximation, based on some sort of assumptions. What you suggest, if done in an appropriate way, is one such approximation. Can you state what assumption you would be making?

If this is for a class, you might need to ask your teacher for clarification, just as, if is it for work, you would ask whoever asked you to do this. Your answer has to reflect their goals, so you need to know what they are.