Answer:
He should spend 3 minutes or less on each scale
Sven made a mistake in the symbol of inequality, placing lesser or equal instead of greater or equal
Explanation:
Let
t ------> is the number of minutes he spends on each scale
Remember that the phrase "at least" is equal to "greater than or equal"
so
The inequality that represent this scenario is

solve for t


Multiply by -1 both sides

Divide by 5 both sides

Sven is incorrect
He should spend 3 minutes or less on each scale
Sven made a mistake in the symbol of inequality, placing lesser or equal instead of greater or equal