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There are 88 three bedroom units and 112 four bedroom units.

Step-by-step explanation:

Let x be the number of three-bedroom units and y be the number of  four-bedroom units.

Then, we have the following system of equations :-

Multiply 4 on both sides of the equation(1), we get

Eliminate (2) from (3)

Put x=88 in (1), we get

Hence, there are 88 three bedroom units and 112 four bedroom units.