The smart people with the high IQ level that they are looking for would be able to work that out in a flash (seriously).
It's how you look at it... like how the hell am I going to work it out versus, "oh yeah, 1/8th is simply a half then a half, then a half."
This is pretty standard stuff for armed forces, police, justice and government departments nowadays so once you've practiced a bit, they are a piece of cake. Most of these types of jobs now include an initial exam, on-line application where you sell yourself, a one-way video interview with half a dozen questions, if no initial exam then an online test including abstract reasoning, numerical comparisons and verbal reasoning, followed by a selection day consisting of group activities and typing speed and computer activities, psychometric, then followed by a panel interview. Not to mention pre-employment medical, police check and in-depth reference checks.
Gaining employment these days is not what it use to be!