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Area of larger rectangle = PQ x 12 = 66 then PQ = 5.5
BC = 5.5 Perimeter of smaller rectangle = 30 = 2 *BC + 2*AB
30 = 2(5.5) + 2 AB You can take it from here !
PQ=5.5
So, 30 minus 5.5 times 2 is 19,
19/2 will be our answer.