Based on programming rules it’d be 16 from operator precedence.
However, when writing equations in textbooks I notice there is minimization of divisor signs for clarity.
E.g. if I want to say that a times b, is divided by c times d I would write
ab / cd
not
a / c * b / d
Which is the same in terms of operator precedence.
Of course if you’re teaching fractions in grade school you’d use the second as an example.
“E.g. if I want to say that a times b, is divided by c times d I would write
ab / cd”
To start with your sentence is ambiguous. You realize that now, don’t you?
The “ab/cd” means a * b / c * d which is evaluated left to right:
multiply a by b
divide that result by c
multiply that result by d