Answer:
[tex] \huge \colorbox{blue}{16 students}[/tex]
Step-by-step explanation:
we are given the ratio of students and teachers:
[tex] \displaystyle \: \frac{21}{4} [/tex]
which means if the number of students is 21 then the number of teachers should be 4
to find how many teachers should go if students 84 we have to divide 84 by [tex]21/4[/tex] :
[tex] \displaystyle \: 84 \div \frac{21}{4} [/tex]
simplify division:
[tex] = \displaystyle \: 84 \times \frac{4}{21} [/tex]
simplify multiplication:
[tex] = \displaystyle \: \cancel{ 84} \: ^{4} \times \frac{4}{ \cancel{21}} \\ = 4 \times 4 \\ = 16 [/tex]
