# Week 1: Two mistakes in video "Motivation to Derivatives - Part I"

In the 3rd quiz in the video, there are two mistakes

1. In the sentence “What was the average velocitu of the car on the interval from 10 to 15 seconds?” it should say “velocity” not “velocitu”

2. In the explanation, it says " y(15) - y(10) / 5s = 202m - 122m / 5 s = 80m/5s = 16m/s." but it should be “(y(15) - y(10)) / 5s = (202m - 122m) / 5 s = 80m/5s = 16m/s” – the parentheses are missing.

Thanks @Sebastian6 Let me check this.

Dear Sebastian6,

1. I am not seeing the issue that you are describing. Please refer to this image:

1. Can you please confirm if the second issue is here or where?

Strange! It shows up for me, see the screenshots below:

I am not sure if you are seeing a previous version of the course because of a cache issue. Can you please logout from coursera, then open an incognito window and finally access course in the incognito windows and check if you are still seeing the same information?

I am getting the same in an incognito window. I guess it might be related to Safari then.

Yes, can you try in google chrome and let me know if you are getting the same error?

Getting the same issue in Chrome. Weird that your’s is different. Not sure what the explanation could be.

Anyhow, do not worry about it. It has been fixed.

Thanks for reporting this.