Answer:
178 more boys at Barlow School
Step-by-step explanation:
At Barlow, there are ...
(4/9)(873) = 388 . . . . boys
At Willow, 1 -2/3 = 1/3 of the students are boys.
(1/3)(630) = 210 . . . . boys
There are 388 -210 = 178 more boys at Barlow School.
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Additional comment
Strictly speaking a question like this is not "politically correct," as it requires you to assume binary gender identification. Knowing the number of students and the number of girls does not mean we know the number of boys in the real world.
