That

[Progress]

I would like to ask native speakers of English the following thing.

The average life span of British males increased from 48 in 1901 to 75 in 2000, while that of females from 49 to 80.

The question is what that stands for. Of course it means the average life span but strictly the word British isn’t included. So should we say that stands for the average British life span? What is the correct answer?

Thank you very much

 

[Anglika]

It is "The average life span of British males", so that = "the average life-span of British females".

 

[Progress]

Thank you Anglika

But the quize in the text book is:

While that of females (increased) from 49 to 80 that =

In that case, what is the correct answer? just the average life span is enough? or should it be the average British life span?

 

[Anglika]

The average life span of [British] females

However, having thought again, your answer will probably be acceptably "the average life span". If you wanted to be absolutely sure, include the rest.

 

[Progress]

Thank you very much, Anglika.