There are an equal number of boys and girls in a school.
1/3 of the boys and 3/5 of the girls wear spectacles.
There are 252 boys and girls who wear spectacles.
How many boys and girls are there in the school altogether?

Answer: C. 540

Let x be the number of boys and also the number of girls.
(1/3)x + (3/5)x = 252
(5/15)x + (9/15)x = 252
14/15x = 252
x = 270
Total students = 270 boys + 270 girls = 540.

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