what is the difference between 'per' and 'each'?

Question

What is the difference between 'per' & 'each'?

Give example(s) plz.

Answer 1

Per should not replace each or a, but should be reserved for scientific, financial and business writing, and for expressing ratios. Since per means each, it is redundant to write per each. The Latin word per is encountered in phrases such as per diem and per capita.

• Carlos and Ken paid $12 each (not $12 per person) to rent skates for the afternoon.
• The high-tech firm indicated gains of eight cents per share in the second quarter.
• The speed limit on that secondary road is 80 kilometres per hour.
• The water analyst counting bacteria in parts per million is paid the usual per diem (daily) rate.
• Non-standard usage:
  The basketball coach allotted two uniforms per each player.
• Standard usage:
  The basketball coach allotted two uniforms for each player.
  The basketball coach allotted the players two uniforms each.

Answer 2

 

I earn $500 each month
I earn $500 per month

 

The latter describes your salary: if you sit at your desk and don't get fired, you'll get $500. The former is more a description of the situation: somehow, by hook or by crook, I manage to scrape together $500.

The use of "per" imply a causal connection between the passage of time and the arrival of your pay. "Each" encompasses the possibility there's no connection, and it's just happenstance.