In fact, once a number is itself, once 2 is 2. It means "share". A number once is itself, of course!

From a mathematical point of view, it does not mean that "XX is a double YY" means that XX has a double YY.

And double is understood as 1+ 1 times, which can be understood as follows: double is twice, of course twice!

Strictly speaking, this is a narrative problem:

(1)A is q times that of B.

(2)A' is q times larger than B'

There is a difference. In (1), if B= 1,

Q=2 then A= 1*2=2.

And in (2), the same B= 1.

Q=2

But A= 1*( 1+2)=3.

The difference lies in the difference between "yes" and "many". If you change "many" to "yes", you should add one to the multiple, as shown in the figure; (The string is double)

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1 time

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Twice as much as "-"and 2- 1= 1 times as much as "-"

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Twice as much as "-",yes

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"2+ 1=3 times.

Then, the difference between double and double can be understood as the difference between one copy and two copies.