The last model,
It represents 8/10 or 4/5 which is greater than 3/5
We know:

We have

Substitute:


Only 4 and 10 meet the requirements of the question.
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40 and 1 NOT, because 40 > 12
20 and 2 NOT, because 20 > 12
5 and 8 NOT because GCF(5, 8) = 1
The person would have scored 39 out of 50. Hope this helps