The operation * cannot accept the arguments: ,[0.15 -0.38].[-7.1]

I am having this problem. Please help :( When I remove the set ImageSprint, the error is gone then. Is it that imageSprint X and Y can't accept decimals?

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use Do it to debug your blocks, see tip 4 here

Top 5 Tips: How to learn App Inventor

as you can see from the error message, the second item from your list are the 2 values 0.15 -0.38

to be able to multiply, you obviously need only one value...

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Also see https://puravidaapps.com/snippets.php#2parse

for how to deal with variable length input with markup.

parse.aia

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