Answer:
22
Explanation:
Let x represent the number of houses on each street. Normally, Jake delivers 7x papers, and Ryan delivers 3x papers. On the day when Ryan delivered 45 of Jake's papers, we have ...
(3x +45) > (7x -45)
90 > 4x . . . . . . . . . . . add 45 -3x to both sides
22.5 > x . . . . . . . . . . divide by 4
The number of houses on each street will be an integer, so the maximum number of houses on each street is 22.
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Additional comment
If Jake normally delivers more than 45 papers, then we must also have ...
7x > 45
x > 6 3/7
There must be at least 7 houses on each street.