2/5, 1/10, and 1/20 are all less than 1/2
48 ten units and 1 five unit.
The number of bottles in a full box is 12.
<u><em>Explanation</em></u>
Suppose, the number of bottles in a full box is 
So, the number of bottles in <u>three</u> full boxes 
Now, two more boxes are added, both of which have <u>one fewer bottle than the other three</u>. So, the number of bottles in these two boxes 
As there were 9 bottles initially and now there are 67 bottles in the fridge, <em><u>so the equation will be</u></em>....

Thus, the number of bottles in a full box is 12.
Answer:
the first and second one
Step-by-step explanation:
the two last ones go over budget
1) 20×30=600 30×50=1500 total is 2100
2)50×30=1500 10×50= 500 total is 2000
3) 40×30=1200 40×50=2000 total is 3100>over budget.
4) 20×30=600 60×50=3000 total is 3600> way over budget.