Hi
** ScratchJr is a visual programming language designed to introduce programming skills to children ages 5–7 **
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Which is grammatically correct:
1- In tenths of seconds. <— with “s”
2- In tenths of second. <— without “s”
Thank you
ScratchJr - Coding Blocks Guide
“In tenths of a second.”
You are talking about a unit of measure that is one tenth of a second.
Thank you so much, Arinker 
Very nice.
Here’s another one:
The jury decided to choose him as the winner, even though he’d played some of his notes one hundredth of a second too short.
P.s.: I can assure you that they are able to do that. I had a musical training and it was very HAAAAAAAAARD.
Thank you so much, Masme
Very nice.
