Answer:
233
Explanation:
Jerome wants to find b such that ...
cost of di water bottles ≤ 300
1.2b + 20 ≤ 300 . . . . . . substitute expression for cost
1.2b ≤ 280 . . . . . . . . . . subtract 20
b ≤ 280/1.2 = 233 1/3
The maximum number of water bottles Jerome can order is 233.
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We assume Jerome cannot order 1/3 of a bottle.