Recently I was watching 8 out of 10 cats does countdown (S18E01 - 26 July 2019), for which the math question there was the following numbers:
if you haven't seen countdown, you are provided 6 numbers, in which can only use one number once, and can only use the operators; add, subtract, multiply and divide, in order to reach a particular number.
The numbers were [25, 50, 10, 7, 7, 6], and the target was 931.
None of the contestants got the answer (Jon Richardson was close with 932). The host Jimmy Carr asked Rachel Riley if it could be done, to which she responded
It wasn't easy, but I found three ways. Example, $25-6=19$, $7\times7=49$ and then multiply them together to get $19\times49=931$.
John Richardson then jokingly asked; "Did you do that on your 19 times table, or your 49 times table.".
Rachel replied with:
$7 \times 133$, so $7 \times 7 \times 19$...
To which (in the spirit of comedy) was interrupted.
I'm going to guess the $133$ came from $6*25-10-7$, but I frequently see an ability shown by some people to quickly see combinations of numbers and quickly perform operations.
Are there techniques that one can learn in order to develop this ability, like alternative ways of interpreting numbers or more complex relationships between numbers? Or are some people just blessed with a mind that works that way?