Answer :
Total number of not broken windows is 51 windows
Given that;
Number of big window = 48
Number of small window = 12
Number of broken window = 9
Find:
Total number of not broken windows
Computation:
Total number of not broken windows = Number of big window + Number of small window - Number of broken window
Total number of not broken windows = 48+ 12 - 9
Total number of not broken windows = 60 - 9
Total number of not broken windows = 51 windows
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