Level 4, sample assessment 2, task 1.3

Any ideas what how they got result for task 1.3 in 2nd assessment?
I did everything on excel - so no typo.


1period 2 3 4 5 6
68200 69300 67100 64900 70400 74250
15% 10230 10395 10065 9735 10560 11137.5
35% 23870 24255 23485 22715 24640
45% 30690 31185 30195 29205
95% 78430 103565 132110 129305 133870 139232.5
-5% -3410 -3465 -3355 -3245 -3520 -3712.5


answers: Total sales receipts for period 5 - 138480 My result for per5 133870
and period 6 - 141780 My result for per6 139232.5

What do i do wrong?
No idea how they manage rest of answers.