1) In fact, NO LESS THAN 20 percent of people are injured severely due to car accidents.
2) However, because people whose cars had collided and were severely wounded were occupying the intensive units in the hospital, it took NO FEWER THAN an hour for him to have surgery despite his life threatening condition.
These are two sentences that I wrote in a practice writing, but my teacher (Canadian) said the use of "no less than and no fewer than" didn't make sense.
I thought those are used to describe emphasis of numbers.
Could you someone help me understand why it's wrong so that I can improve my English. Thank you