Having read other threads, they are all out of 140. Horrendous if you look at percentages - my son got 85% but has failed by 5 marks...
I hope this isn't too late to allay some of your feelings, but this figure of 85% is a bit misleading. The following text appeared on the results letter sent out by Bexley Council and I would think that a similar situation exists in the Kent area as well, albeit over 3 tests rather than 4.
Bexley Council wrote:
To put the test scores in context for each of the four tests the minimum score is 70, the maximum is 140 and an average of 100. Therefore for the 4 tests in total the minimum score is 280, the maximum is 560 and the average is 400.
In Bexley, the pass mark is 430 across all the papers (it doesn't matter so much if you have a bad day with one). However, it would seem likely that a child born on September 1st who got every question wrong in one paper would still score 70.