Answer:
350
Step-by-step explanation:
Let [tex]s=[/tex] total number of sixth-grade students.
It is given that 60% of sixth-grade students prefer pizza which is equivalent to 210 sixth-grade students. With this, the following can be written:
[tex]60\%s = 210[/tex]
[tex]0.6s=210[/tex] ([tex]60\%[/tex] can be converted into the decimal form [tex]0.6[/tex])
[tex]s = 210\div 0.6[/tex]
[tex]=350[/tex]
∴ There is a total of 350 sixth-grade students in the school.
Hope this helps :)