AWS: AWS Solutions Architect Associate - Practice

After reading the book AWS Certified Solutions Architect - Official Study Guide i decided to go for a online exam at https://aws.amazon.com/training/

I had to answer 25 question in about 30 minutes, which was quite exhausting. Only a few minutes after the exam i got the following mail:

Hmmm.
3.0 Specify Secure Applications and Architectures: 50%
An unconvincing result for this area, but with some more reading and more exercises i should get above 80%.

4.0 and 5.0 with 100%: Better than expected.

But is an overall score of 76% enough?
One day later inside my aws certification account the following line appeared:

;-)