Let us look at mean weight of cars by repair record and origin

  Car origin
  Domestic Foreign Total
Repair record 1978
  1 3,100 3,100
  2 3,354 3,354
  3 3,442 2,010 3,299
  4 3,532 2,208 2,870
  5 1,960 2,403 2,323
  Total 3,368 2,263 3,032