Given:
[tex]72-\frac{8}{2}+6\times3[/tex]
He does mistake in the order of giving preference.
We should give preference in the order, division, multiplication, addition, subtraction.
But, he gave the first preferrence to the subtraction.
72-8=64
Next, he used division
64/2=32
Next he adds 32 with 8.
So, he gets 50.
But the actual simplification is,
Simplifying we get,
[tex]\begin{gathered} 72-\frac{8}{2}+6\times3=72-4+18 \\ =68+18 \\ =86 \end{gathered}[/tex]
Hence, the correct value of the expression is 86.
