The rule of cold drink shop is: five empty soda bottles can be exchanged for one bottle of soda. A class of students drank 161 bottles of soda, some of which were exchanged with empty bottles left over. So, how many bottles of soda should they buy at least?

According to the stem analysis, you can get (1 + 14) bottles of soda when you buy a bottle of soda, 161 ÷ (1 + 14), = 161 × 45, = 128.8, ≈ 129 (bottles). A: they need to buy at least 129 bottles

Six empty bottles can be exchanged for a bottle of soda. A class drank 136 bottles of soda, some of which were exchanged with empty bottles. How many bottles of soda did they buy at least

113
6 empty bottles can be replaced (note that this bottle includes bottles)
So:
Five empty bottles can be exchanged for a soda without a bottle
So if you buy a bottle, you can actually drink it:
1 + 1 / 5 = 6 / 5 bottles
So at least you need to buy:
136 / (6 / 5) = 113.3 bottles, because there is no decimal, so it is at least 114 bottles

Five empty bottles can be exchanged for one bottle of soda. A class drank 160 bottles of soda, some of which were exchanged with the remaining empty bottles. How many bottles of soda did they buy at least
Water?

1+5+25+125+3+1=160
125+3=128
In the end, I borrowed an empty bottle to make five, changed one and returned it after drinking

A class of students bought 161 bottles of soda, five empty bottles can change a bottle of soda, how many bottles of soda can they drink at most

161 △ 5 = 32, more than 1,
32＋1＝33,
33 ÷ 5 = 6, more than 3,
6＋3＝9,
9 △ 5 = 1,4,
Borrow a 1 + 4 = 5 with others, just change another bottle and give it back to him after drinking
A total of 161 + 32 + 6 + 1 + 1 = 201 bottles were drunk

The rule of cold drink shop is: five empty soda bottles can be exchanged for one bottle of soda. A class of students drank 161 bottles of soda, some of which were exchanged with empty bottles left over. So, how many bottles of soda should they buy at least?