URGENT BRAINLIEST GIVEN Mr Brown gives his class a test. The 10 girls in the class get a mean mark of 70%. The 15 boys in the class get a mean mark of 80%. Nick says that because the mean of 70 and 80 is 75 then the mean mark for the whole class in the test is 75%. Nick is not correct. Is the correct mean less than or greater than 75%? You must justify your answer.