Question

If A = 4 what is the value of the expression 12 - a/4

Answer 1

Put 4 where "a" is and do the arithmetic.
$12-\dfrac{a}{4}=12-\dfrac{4}{4}=12-1=11$

The value of the expression is 11.


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This is very different from
$\dfrac{12-a}{4}=\dfrac{12-4}{4}=\dfrac{8}{4}=2$
In this latter case, parentheses are required when the expression is rendered using plain text: (12 -a)/4.

Answer 2

I hope this helps!!