An open circle means not equal to. So, if your equation is x < 4, You would put an OPEN circle at four because it can't equal four.
I think something wrong
the answer must be 18
Answer: 2,680 bulbs were used in all.
I added all of them up so 1240 + 1350 + 90 which equals 2,680.
If you have any questions let me know, have a great day!
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