Question

The quotient of nine less than 3 times a number and four is 21how to translate into a sentence

Answer 1

Hello,

Let's assume n the number searched.

nine less 3 times n is written 9-3n
 
$\dfrac{9-3n}{4} =21\\ ==\ \textgreater \ 9-3n=84\\ ==\ \textgreater \ -3n=75\\ ==\ \textgreater \ n=-25$