Wow, memories!
I remember having to buy a thing called a 'Calculator' in my first year of Technical School in 1972 (remember Tech schools?).
I went to Blacktown Technical School as an apprentice Electrician.
It was nothing like those flashy HP-35's. It only did: add, subtract, multiply, and divide.
It cost my parents $80 and Dad was only getting about $80 a fortnight pay in the Air Force!!!
It looked exactly like this model but it might have been a different brand. Could've been Casio or Hanimex: