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Light the Lights

Stage: 1 Challenge Level: Challenge Level:2 Challenge Level:2

Thomas of QEGS Wakefield identified the rules:
To light the YELLOW light the rule is: < $30$
To light the RED light the rule is: Have an odd tens digit
To light the BLUE light the rule is: Multiple of $5$
To light the GREEN light the rule is: Is odd 
Ahmad reasoned well to explain the minimum number which lit up all the lights:
The answer is $15$.
Its tens digit is the smallest, from the allowed, which is $10$. Its unit digit is $5$ ; it is not zero because then it would be even and wouldn't light the green. It is also less than $30$.  

Are you both sure that the yellow light only lights up for numbers under $30$?