Can someone answer this for me just tell me what to pick
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The inequality you require is
The number of bottles left at the end of each day is 48 - 3x. So it is:-
48 - 3x < 10
Solving the inequality to find the last part of question:-
-3x < 10 - 48
-3x < -38
x > 38/3 = 12 2/3
So answer is 13 days.