Maria is incorrect as she didn't count the number of zeros properly. After knowing that 6 × 5 = 30, the question is 60×500 which means there are 3 zeros that should be added to the 30 that she got, this will have given her a value of 30,000 which is correct.
She write 3000 which is 3 under thousands rather than 30,000 which is 3 under tens of thousands.
Assuming the pigeons are either male or female, the 45% of them that are not female are male. Of those, there are 40% that are not white, so 60% are white. Then the number of white male pigeons is ...